Updated with master

8 files changed, 746 insertions, 475 deletions

diff --git a/toxav/audio.c b/toxav/audio.c
index c592a7da..f6993a1d 100644
--- a/toxav/audio.c
+++ b/toxav/audio.c
@@ -38,7 +38,7 @@ bool reconfigure_audio_decoder(ACSession* ac, int32_t sampling_rate, int8_t chan
 
 
 
-ACSession* ac_new(ToxAV* av, uint32_t friend_number, toxav_receive_audio_frame_cb *cb, void *cb_data)
+ACSession* ac_new(ToxAV* av, uint32_t friend_number, toxav_audio_receive_frame_cb *cb, void *cb_data)
 {
     ACSession *ac = calloc(sizeof(ACSession), 1);
     
diff --git a/toxav/audio.h b/toxav/audio.h
index c003bac0..9ef10ae4 100644
--- a/toxav/audio.h
+++ b/toxav/audio.h
@@ -61,13 +61,13 @@ typedef struct ACSession_s {
     
     ToxAV* av;
     uint32_t friend_number;
-    PAIR(toxav_receive_audio_frame_cb *, void *) acb; /* Audio frame receive callback */
+    PAIR(toxav_audio_receive_frame_cb *, void *) acb; /* Audio frame receive callback */
 } ACSession;
 
 /*
  * Create new Audio Codec session.
  */
-ACSession* ac_new(ToxAV* av, uint32_t friend_number, toxav_receive_audio_frame_cb *cb, void *cb_data);
+ACSession* ac_new(ToxAV* av, uint32_t friend_number, toxav_audio_receive_frame_cb *cb, void *cb_data);
 /*
  * Kill the Audio Codec session.
  */
diff --git a/toxav/msi.c b/toxav/msi.c
index 65b6c4e4..d3559160 100644
--- a/toxav/msi.c
+++ b/toxav/msi.c
@@ -683,7 +683,7 @@ void handle_push ( MSICall *call, const MSIMessage *msg )
             
             /* Only act if capabilities changed */
             if ( call->peer_capabilities != msg->capabilities.value) {
-                LOGGER_INFO("Friend is changing capabilities");
+                LOGGER_INFO("Friend is changing capabilities to: %u", msg->capabilities.value);
                 
                 call->peer_capabilities = msg->capabilities.value;
                 if ( invoke_callback(call, msi_OnCapabilities) == -1 )
diff --git a/toxav/msi.h b/toxav/msi.h
index 4836ae89..59f32c1d 100644
--- a/toxav/msi.h
+++ b/toxav/msi.h
@@ -50,10 +50,10 @@ typedef enum {
  * Supported capabilities
  */
 typedef enum {
-    msi_CapSAudio = 1, /* sending audio */
-    msi_CapSVideo = 2, /* sending video */
-    msi_CapRAudio = 4, /* receiving audio */
-    msi_CapRVideo = 8, /* receiving video */
+    msi_CapSAudio = 4,  /* sending audio */
+    msi_CapSVideo = 8,  /* sending video */
+    msi_CapRAudio = 16, /* receiving audio */
+    msi_CapRVideo = 32, /* receiving video */
 } MSICapabilities;
 
 
diff --git a/toxav/toxav.c b/toxav/toxav.c
index 5e32f196..7ce6b9bc 100644
--- a/toxav/toxav.c
+++ b/toxav/toxav.c
@@ -91,8 +91,8 @@ struct ToxAV {
     
     PAIR(toxav_call_cb *, void*) ccb; /* Call callback */
     PAIR(toxav_call_state_cb *, void *) scb; /* Call state callback */
-    PAIR(toxav_receive_audio_frame_cb *, void *) acb; /* Audio frame receive callback */
-    PAIR(toxav_receive_video_frame_cb *, void *) vcb; /* Video frame receive callback */
+    PAIR(toxav_audio_receive_frame_cb *, void *) acb; /* Audio frame receive callback */
+    PAIR(toxav_video_receive_frame_cb *, void *) vcb; /* Video frame receive callback */
     PAIR(toxav_audio_bit_rate_status_cb *, void *) abcb; /* Audio bit rate control callback */
     PAIR(toxav_video_bit_rate_status_cb *, void *) vbcb; /* Video bit rate control callback */
     
@@ -122,6 +122,27 @@ void call_kill_transmission(ToxAVCall* call);
 void ba_set(ToxAvBitrateAdapter* ba, uint32_t bit_rate);
 bool ba_shoud_send_dummy(ToxAvBitrateAdapter* ba);
 
+uint32_t toxav_version_major(void)
+{
+    return 0;
+}
+uint32_t toxav_version_minor(void)
+{
+    return 0;
+}
+uint32_t toxav_version_patch(void)
+{
+    return 0;
+}
+bool toxav_version_is_compatible(uint32_t major, uint32_t minor, uint32_t patch)
+{
+    (void)major;
+    (void)minor;
+    (void)patch;
+    
+    return 1;
+}
+
 ToxAV* toxav_new(Tox* tox, TOXAV_ERR_NEW* error)
 {
     TOXAV_ERR_NEW rc = TOXAV_ERR_NEW_OK;
@@ -204,7 +225,7 @@ void toxav_kill(ToxAV* av)
     free(av);
 }
 
-Tox* toxav_get_tox(ToxAV* av)
+Tox* toxav_get_tox(const ToxAV* av)
 {
     return (Tox*) av->m;
 }
@@ -430,20 +451,14 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
         goto END;
     }
     
-    
     ToxAVCall* call = call_get(av, friend_number);
-    if (call == NULL) {
+    if (call == NULL || (!call->active && control != TOXAV_CALL_CONTROL_CANCEL)) {
         rc = TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_IN_CALL;
         goto END;
     }
     
     switch (control) {
         case TOXAV_CALL_CONTROL_RESUME: {
-            if (!call->active) {
-                rc = TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_IN_CALL;
-                goto END;
-            }
-            
             /* Only act if paused and had media transfer active before */
             if (call->msi_call->self_capabilities == 0 && 
                 call->previous_self_capabilities ) {
@@ -459,17 +474,12 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
                 rtp_start_receiving(call->audio.first);
                 rtp_start_receiving(call->video.first);
             } else {
-                rc = TOXAV_ERR_CALL_CONTROL_NOT_PAUSED;
+                rc = TOXAV_ERR_CALL_CONTROL_INVALID_TRANSITION;
                 goto END;
             }
         } break;
         
         case TOXAV_CALL_CONTROL_PAUSE: {
-            if (!call->active) {
-                rc = TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_IN_CALL;
-                goto END;
-            }
-            
             /* Only act if not already paused */
             if (call->msi_call->self_capabilities) {
                 call->previous_self_capabilities = call->msi_call->self_capabilities;
@@ -484,7 +494,7 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
                 rtp_stop_receiving(call->audio.first);
                 rtp_stop_receiving(call->video.first);
             } else {
-                rc = TOXAV_ERR_CALL_CONTROL_ALREADY_PAUSED;
+                rc = TOXAV_ERR_CALL_CONTROL_INVALID_TRANSITION;
                 goto END;
             }
         } break;
@@ -498,12 +508,7 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
             call_remove(call);
         } break;
         
-        case TOXAV_CALL_CONTROL_TOGGLE_MUTE_AUDIO: {
-            if (!call->active) {
-                rc = TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_IN_CALL;
-                goto END;
-            }
-            
+        case TOXAV_CALL_CONTROL_MUTE_AUDIO: {
             if (call->msi_call->self_capabilities & msi_CapRAudio) {
                 if (msi_change_capabilities(call->msi_call, call->
                     msi_call->self_capabilities ^ msi_CapRAudio) == -1) {
@@ -515,9 +520,13 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
                 
                 rtp_stop_receiving(call->audio.first);
             } else {
-                /* This call was already muted so notify the friend that he can
-                 * start sending audio again
-                 */
+                rc = TOXAV_ERR_CALL_CONTROL_INVALID_TRANSITION;
+                goto END;
+            }
+        } break;
+        
+        case TOXAV_CALL_CONTROL_UNMUTE_AUDIO: {
+            if (call->msi_call->self_capabilities ^ msi_CapRAudio) {
                 if (msi_change_capabilities(call->msi_call, call->
                     msi_call->self_capabilities | msi_CapRAudio) == -1) {
                     /* The only reason for this function to fail is invalid state 
@@ -527,15 +536,13 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
                 }
                 
                 rtp_start_receiving(call->audio.first);
+            } else {
+                rc = TOXAV_ERR_CALL_CONTROL_INVALID_TRANSITION;
+                goto END;
             }
         } break;
         
-        case TOXAV_CALL_CONTROL_TOGGLE_HIDE_VIDEO: {
-            if (!call->active) {
-                rc = TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_IN_CALL;
-                goto END;
-            }
-            
+        case TOXAV_CALL_CONTROL_HIDE_VIDEO: {
             if (call->msi_call->self_capabilities & msi_CapRVideo) {
                 if (msi_change_capabilities(call->msi_call, call->
                     msi_call->self_capabilities ^ msi_CapRVideo) == -1) {
@@ -547,9 +554,13 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
                 
                 rtp_stop_receiving(call->video.first);
             } else {
-                /* This call was already muted so notify the friend that he can
-                 * start sending video again
-                 */
+                rc = TOXAV_ERR_CALL_CONTROL_INVALID_TRANSITION;
+                goto END;
+            }
+        } break;
+        
+        case TOXAV_CALL_CONTROL_SHOW_VIDEO: {
+            if (call->msi_call->self_capabilities ^ msi_CapRVideo) {
                 if (msi_change_capabilities(call->msi_call, call->
                     msi_call->self_capabilities | msi_CapRVideo) == -1) {
                     /* The only reason for this function to fail is invalid state 
@@ -558,7 +569,10 @@ bool toxav_call_control(ToxAV* av, uint32_t friend_number, TOXAV_CALL_CONTROL co
                     goto END;
                 }
                 
-                rtp_start_receiving(call->video.first);
+                rtp_start_receiving(call->audio.first);
+            } else {
+                rc = TOXAV_ERR_CALL_CONTROL_INVALID_TRANSITION;
+                goto END;
             }
         } break;
     }
@@ -572,26 +586,26 @@ END:
     return rc == TOXAV_ERR_CALL_CONTROL_OK;
 }
 
-void toxav_callback_video_bit_rate_status(ToxAV* av, toxav_video_bit_rate_status_cb* function, void* user_data)
+void toxav_callback_audio_bit_rate_status(ToxAV* av, toxav_audio_bit_rate_status_cb* function, void* user_data)
 {
     pthread_mutex_lock(av->mutex);
-    av->vbcb.first = function;
-    av->vbcb.second = user_data;
+    av->abcb.first = function;
+    av->abcb.second = user_data;
     pthread_mutex_unlock(av->mutex);
 }
 
-bool toxav_set_video_bit_rate(ToxAV* av, uint32_t friend_number, uint32_t video_bit_rate, bool force, TOXAV_ERR_BIT_RATE* error)
+bool toxav_audio_bit_rate_set(ToxAV* av, uint32_t friend_number, uint32_t audio_bit_rate, bool force, TOXAV_ERR_SET_BIT_RATE* error)
 {
-    TOXAV_ERR_BIT_RATE rc = TOXAV_ERR_BIT_RATE_OK;
+    TOXAV_ERR_SET_BIT_RATE rc = TOXAV_ERR_SET_BIT_RATE_OK;
     ToxAVCall* call;
     
     if (m_friend_exists(av->m, friend_number) == 0) {
-        rc = TOXAV_ERR_BIT_RATE_FRIEND_NOT_FOUND;
+        rc = TOXAV_ERR_SET_BIT_RATE_FRIEND_NOT_FOUND;
         goto END;
     }
     
-    if (video_bit_rate_invalid(video_bit_rate)) {
-        rc = TOXAV_ERR_BIT_RATE_INVALID;
+    if (audio_bit_rate_invalid(audio_bit_rate)) {
+        rc = TOXAV_ERR_SET_BIT_RATE_INVALID;
         goto END;
     }
     
@@ -599,26 +613,27 @@ bool toxav_set_video_bit_rate(ToxAV* av, uint32_t friend_number, uint32_t video_
     call = call_get(av, friend_number);
     if (call == NULL || !call->active || call->msi_call->state != msi_CallActive) {
         pthread_mutex_unlock(av->mutex);
-        rc = TOXAV_ERR_BIT_RATE_FRIEND_NOT_IN_CALL;
+        rc = TOXAV_ERR_SET_BIT_RATE_FRIEND_NOT_IN_CALL;
         goto END;
     }
     
-    if (call->video_bit_rate == video_bit_rate || (call->vba.active && call->vba.bit_rate == video_bit_rate)) {
+    if (call->audio_bit_rate == audio_bit_rate || (call->aba.active && call->aba.bit_rate == audio_bit_rate)) {
         pthread_mutex_unlock(av->mutex);
         goto END;
     }
     
+    
     pthread_mutex_lock(call->mutex);
     
-    if (video_bit_rate > call->video_bit_rate && !force)
-        ba_set(&call->vba, video_bit_rate);
+    if (audio_bit_rate > call->audio_bit_rate && !force)
+        ba_set(&call->aba, audio_bit_rate);
     else {
         /* Cancel any previous non forceful bitrate change request */
-        memset(&call->vba, 0, sizeof(call->vba));
-        call->video_bit_rate = video_bit_rate;
+        memset(&call->aba, 0, sizeof(call->aba));
+        call->audio_bit_rate = audio_bit_rate;
         
-        if (!force && av->vbcb.first) 
-            av->vbcb.first (av, call->friend_number, true, video_bit_rate, av->vbcb.second);
+        if (!force && av->abcb.first) 
+            av->abcb.first (av, call->friend_number, true, audio_bit_rate, av->abcb.second);
     }
     
     pthread_mutex_unlock(call->mutex);
@@ -628,29 +643,29 @@ END:
     if (error)
         *error = rc;
     
-    return rc == TOXAV_ERR_BIT_RATE_OK;
+    return rc == TOXAV_ERR_SET_BIT_RATE_OK;
 }
 
-void toxav_callback_audio_bit_rate_status(ToxAV* av, toxav_audio_bit_rate_status_cb* function, void* user_data)
+void toxav_callback_video_bit_rate_status(ToxAV* av, toxav_video_bit_rate_status_cb* function, void* user_data)
 {
     pthread_mutex_lock(av->mutex);
-    av->abcb.first = function;
-    av->abcb.second = user_data;
+    av->vbcb.first = function;
+    av->vbcb.second = user_data;
     pthread_mutex_unlock(av->mutex);
 }
 
-bool toxav_set_audio_bit_rate(ToxAV* av, uint32_t friend_number, uint32_t audio_bit_rate, bool force, TOXAV_ERR_BIT_RATE* error)
+bool toxav_video_bit_rate_set(ToxAV* av, uint32_t friend_number, uint32_t video_bit_rate, bool force, TOXAV_ERR_SET_BIT_RATE* error)
 {
-    TOXAV_ERR_BIT_RATE rc = TOXAV_ERR_BIT_RATE_OK;
+    TOXAV_ERR_SET_BIT_RATE rc = TOXAV_ERR_SET_BIT_RATE_OK;
     ToxAVCall* call;
     
     if (m_friend_exists(av->m, friend_number) == 0) {
-        rc = TOXAV_ERR_BIT_RATE_FRIEND_NOT_FOUND;
+        rc = TOXAV_ERR_SET_BIT_RATE_FRIEND_NOT_FOUND;
         goto END;
     }
     
-    if (audio_bit_rate_invalid(audio_bit_rate)) {
-        rc = TOXAV_ERR_BIT_RATE_INVALID;
+    if (video_bit_rate_invalid(video_bit_rate)) {
+        rc = TOXAV_ERR_SET_BIT_RATE_INVALID;
         goto END;
     }
     
@@ -658,27 +673,26 @@ bool toxav_set_audio_bit_rate(ToxAV* av, uint32_t friend_number, uint32_t audio_
     call = call_get(av, friend_number);
     if (call == NULL || !call->active || call->msi_call->state != msi_CallActive) {
         pthread_mutex_unlock(av->mutex);
-        rc = TOXAV_ERR_BIT_RATE_FRIEND_NOT_IN_CALL;
+        rc = TOXAV_ERR_SET_BIT_RATE_FRIEND_NOT_IN_CALL;
         goto END;
     }
     
-    if (call->audio_bit_rate == audio_bit_rate || (call->aba.active && call->aba.bit_rate == audio_bit_rate)) {
+    if (call->video_bit_rate == video_bit_rate || (call->vba.active && call->vba.bit_rate == video_bit_rate)) {
         pthread_mutex_unlock(av->mutex);
         goto END;
     }
     
-    
     pthread_mutex_lock(call->mutex);
     
-    if (audio_bit_rate > call->audio_bit_rate && !force)
-        ba_set(&call->aba, audio_bit_rate);
+    if (video_bit_rate > call->video_bit_rate && !force)
+        ba_set(&call->vba, video_bit_rate);
     else {
         /* Cancel any previous non forceful bitrate change request */
-        memset(&call->aba, 0, sizeof(call->aba));
-        call->audio_bit_rate = audio_bit_rate;
+        memset(&call->vba, 0, sizeof(call->vba));
+        call->video_bit_rate = video_bit_rate;
         
-        if (!force && av->abcb.first) 
-            av->abcb.first (av, call->friend_number, true, audio_bit_rate, av->abcb.second);
+        if (!force && av->vbcb.first) 
+            av->vbcb.first (av, call->friend_number, true, video_bit_rate, av->vbcb.second);
     }
     
     pthread_mutex_unlock(call->mutex);
@@ -688,10 +702,112 @@ END:
     if (error)
         *error = rc;
     
-    return rc == TOXAV_ERR_BIT_RATE_OK;
+    return rc == TOXAV_ERR_SET_BIT_RATE_OK;
 }
 
-bool toxav_send_video_frame(ToxAV* av, uint32_t friend_number, uint16_t width, uint16_t height, const uint8_t* y, const uint8_t* u, const uint8_t* v, TOXAV_ERR_SEND_FRAME* error)
+bool toxav_audio_send_frame(ToxAV* av, uint32_t friend_number, const int16_t* pcm, size_t sample_count, uint8_t channels, uint32_t sampling_rate, TOXAV_ERR_SEND_FRAME* error)
+{
+    TOXAV_ERR_SEND_FRAME rc = TOXAV_ERR_SEND_FRAME_OK;
+    ToxAVCall* call;
+    
+    if (m_friend_exists(av->m, friend_number) == 0) {
+        rc = TOXAV_ERR_SEND_FRAME_FRIEND_NOT_FOUND;
+        goto END;
+    }
+    
+    pthread_mutex_lock(av->mutex);
+    call = call_get(av, friend_number);
+    if (call == NULL || !call->active || call->msi_call->state != msi_CallActive) {
+        pthread_mutex_unlock(av->mutex);
+        rc = TOXAV_ERR_SEND_FRAME_FRIEND_NOT_IN_CALL;
+        goto END;
+    }
+    
+    pthread_mutex_lock(call->mutex_audio);
+    pthread_mutex_unlock(av->mutex);
+    
+    if ( pcm == NULL ) {
+        pthread_mutex_unlock(call->mutex_audio);
+        rc = TOXAV_ERR_SEND_FRAME_NULL;
+        goto END;
+    }
+    
+    if ( channels > 2 ) {
+        pthread_mutex_unlock(call->mutex_audio);
+        rc = TOXAV_ERR_SEND_FRAME_INVALID;
+        goto END;
+    }
+    
+    { /* Encode and send */
+        if (ac_reconfigure_encoder(call->audio.second, call->audio_bit_rate * 1000, sampling_rate, channels) != 0) {
+            pthread_mutex_unlock(call->mutex_audio);
+            rc = TOXAV_ERR_SEND_FRAME_INVALID;
+            goto END;
+        }
+        
+        uint8_t dest[sample_count + sizeof(sampling_rate)]; /* This is more than enough always */
+        
+        sampling_rate = htonl(sampling_rate);
+        memcpy(dest, &sampling_rate, sizeof(sampling_rate));
+        int vrc = opus_encode(call->audio.second->encoder, pcm, sample_count,
+                              dest + sizeof(sampling_rate), sizeof(dest) - sizeof(sampling_rate));
+        
+        if (vrc < 0) {
+            LOGGER_WARNING("Failed to encode frame %s", opus_strerror(vrc));
+            pthread_mutex_unlock(call->mutex_audio);
+            rc = TOXAV_ERR_SEND_FRAME_INVALID;
+            goto END;
+        }
+        
+        if (rtp_send_data(call->audio.first, dest, vrc + sizeof(sampling_rate), false) != 0) {
+            LOGGER_WARNING("Failed to send audio packet");
+            rc = TOXAV_ERR_SEND_FRAME_RTP_FAILED;
+        }
+        
+        
+        /* For bit rate measurement; send dummy packet */
+        if (ba_shoud_send_dummy(&call->aba)) {
+            sampling_rate = ntohl(sampling_rate);
+            if (ac_reconfigure_test_encoder(call->audio.second, call->audio_bit_rate * 1000, sampling_rate, channels) != 0) {
+                /* FIXME should the bit rate changing fail here? */
+                pthread_mutex_unlock(call->mutex_audio);
+                rc = TOXAV_ERR_SEND_FRAME_INVALID;
+                goto END;
+            }
+            
+            sampling_rate = htonl(sampling_rate);
+            memcpy(dest, &sampling_rate, sizeof(sampling_rate));
+            vrc = opus_encode(call->audio.second->test_encoder, pcm, sample_count,
+                                dest + sizeof(sampling_rate), sizeof(dest) - sizeof(sampling_rate));
+            
+            if (vrc < 0) {
+                LOGGER_WARNING("Failed to encode frame %s", opus_strerror(vrc));
+                pthread_mutex_unlock(call->mutex_audio);
+                rc = TOXAV_ERR_SEND_FRAME_INVALID;
+                goto END;
+            }
+            
+            if (rtp_send_data(call->audio.first, dest, vrc + sizeof(sampling_rate), true) != 0) {
+                LOGGER_WARNING("Failed to send audio packet");
+                rc = TOXAV_ERR_SEND_FRAME_RTP_FAILED;
+            }
+            
+            if (call->aba.end_time == (uint64_t) ~0)
+                call->aba.end_time = current_time_monotonic() + BITRATE_CHANGE_TESTING_TIME_MS;
+        }
+    }
+    
+    
+    pthread_mutex_unlock(call->mutex_audio);
+    
+END:
+    if (error)
+        *error = rc;
+    
+    return rc == TOXAV_ERR_SEND_FRAME_OK;
+}
+
+bool toxav_video_send_frame(ToxAV* av, uint32_t friend_number, uint16_t width, uint16_t height, const uint8_t* y, const uint8_t* u, const uint8_t* v, const uint8_t* a,TOXAV_ERR_SEND_FRAME* error)
 {
     TOXAV_ERR_SEND_FRAME rc = TOXAV_ERR_SEND_FRAME_OK;
     ToxAVCall* call;
@@ -736,6 +852,10 @@ bool toxav_send_video_frame(ToxAV* av, uint32_t friend_number, uint16_t width, u
         memcpy(img.planes[VPX_PLANE_U], u, (width/2) * (height/2));
         memcpy(img.planes[VPX_PLANE_V], v, (width/2) * (height/2));
         
+        /* TODO LOL */
+        if (a && img.planes[VPX_PLANE_ALPHA])
+            memcpy(img.planes[VPX_PLANE_ALPHA], a, width * height);
+        
         int vrc = vpx_codec_encode(call->video.second->encoder, &img, 
                                    call->video.second->frame_counter, 1, 0, MAX_ENCODE_TIME_US);
         
@@ -856,109 +976,15 @@ END:
     return rc == TOXAV_ERR_SEND_FRAME_OK;
 }
 
-bool toxav_send_audio_frame(ToxAV* av, uint32_t friend_number, const int16_t* pcm, size_t sample_count, uint8_t channels, uint32_t sampling_rate, TOXAV_ERR_SEND_FRAME* error)
+void toxav_callback_audio_receive_frame(ToxAV* av, toxav_audio_receive_frame_cb* function, void* user_data)
 {
-    TOXAV_ERR_SEND_FRAME rc = TOXAV_ERR_SEND_FRAME_OK;
-    ToxAVCall* call;
-    
-    if (m_friend_exists(av->m, friend_number) == 0) {
-        rc = TOXAV_ERR_SEND_FRAME_FRIEND_NOT_FOUND;
-        goto END;
-    }
-    
     pthread_mutex_lock(av->mutex);
-    call = call_get(av, friend_number);
-    if (call == NULL || !call->active || call->msi_call->state != msi_CallActive) {
-        pthread_mutex_unlock(av->mutex);
-        rc = TOXAV_ERR_SEND_FRAME_FRIEND_NOT_IN_CALL;
-        goto END;
-    }
-    
-    pthread_mutex_lock(call->mutex_audio);
+    av->acb.first = function;
+    av->acb.second = user_data;
     pthread_mutex_unlock(av->mutex);
-    
-    if ( pcm == NULL ) {
-        pthread_mutex_unlock(call->mutex_audio);
-        rc = TOXAV_ERR_SEND_FRAME_NULL;
-        goto END;
-    }
-    
-    if ( channels > 2 ) {
-        pthread_mutex_unlock(call->mutex_audio);
-        rc = TOXAV_ERR_SEND_FRAME_INVALID;
-        goto END;
-    }
-    
-    { /* Encode and send */
-        if (ac_reconfigure_encoder(call->audio.second, call->audio_bit_rate * 1000, sampling_rate, channels) != 0) {
-            pthread_mutex_unlock(call->mutex_audio);
-            rc = TOXAV_ERR_SEND_FRAME_INVALID;
-            goto END;
-        }
-        
-        uint8_t dest[sample_count + sizeof(sampling_rate)]; /* This is more than enough always */
-        
-        sampling_rate = htonl(sampling_rate);
-        memcpy(dest, &sampling_rate, sizeof(sampling_rate));
-        int vrc = opus_encode(call->audio.second->encoder, pcm, sample_count,
-                              dest + sizeof(sampling_rate), sizeof(dest) - sizeof(sampling_rate));
-        
-        if (vrc < 0) {
-            LOGGER_WARNING("Failed to encode frame %s", opus_strerror(vrc));
-            pthread_mutex_unlock(call->mutex_audio);
-            rc = TOXAV_ERR_SEND_FRAME_INVALID;
-            goto END;
-        }
-        
-                if (rtp_send_data(call->audio.first, dest, vrc + sizeof(sampling_rate), false) != 0) {
-                        LOGGER_WARNING("Failed to send audio packet");
-                        rc = TOXAV_ERR_SEND_FRAME_RTP_FAILED;
-                }
-                
-                
-        /* For bit rate measurement; send dummy packet */
-        if (ba_shoud_send_dummy(&call->aba)) {
-            sampling_rate = ntohl(sampling_rate);
-            if (ac_reconfigure_test_encoder(call->audio.second, call->audio_bit_rate * 1000, sampling_rate, channels) != 0) {
-                /* FIXME should the bit rate changing fail here? */
-                pthread_mutex_unlock(call->mutex_audio);
-                rc = TOXAV_ERR_SEND_FRAME_INVALID;
-                goto END;
-            }
-            
-            sampling_rate = htonl(sampling_rate);
-            memcpy(dest, &sampling_rate, sizeof(sampling_rate));
-            vrc = opus_encode(call->audio.second->test_encoder, pcm, sample_count,
-                                dest + sizeof(sampling_rate), sizeof(dest) - sizeof(sampling_rate));
-            
-            if (vrc < 0) {
-                LOGGER_WARNING("Failed to encode frame %s", opus_strerror(vrc));
-                pthread_mutex_unlock(call->mutex_audio);
-                rc = TOXAV_ERR_SEND_FRAME_INVALID;
-                goto END;
-            }
-            
-            if (rtp_send_data(call->audio.first, dest, vrc + sizeof(sampling_rate), true) != 0) {
-                LOGGER_WARNING("Failed to send audio packet");
-                rc = TOXAV_ERR_SEND_FRAME_RTP_FAILED;
-            }
-            
-            if (call->aba.end_time == (uint64_t) ~0)
-                call->aba.end_time = current_time_monotonic() + BITRATE_CHANGE_TESTING_TIME_MS;
-        }
-    }
-    
-    
-    pthread_mutex_unlock(call->mutex_audio);
-    
-END:
-    if (error)
-        *error = rc;
-    
-    return rc == TOXAV_ERR_SEND_FRAME_OK;
 }
 
-void toxav_callback_receive_video_frame(ToxAV* av, toxav_receive_video_frame_cb* function, void* user_data)
+void toxav_callback_video_receive_frame(ToxAV* av, toxav_video_receive_frame_cb* function, void* user_data)
 {
     pthread_mutex_lock(av->mutex);
     av->vcb.first = function;
@@ -966,14 +992,6 @@ void toxav_callback_receive_video_frame(ToxAV* av, toxav_receive_video_frame_cb*
     pthread_mutex_unlock(av->mutex);
 }
 
-void toxav_callback_receive_audio_frame(ToxAV* av, toxav_receive_audio_frame_cb* function, void* user_data)
-{
-    pthread_mutex_lock(av->mutex);
-    av->acb.first = function;
-    av->acb.second = user_data;
-    pthread_mutex_unlock(av->mutex);
-}
-
 
 /*******************************************************************************
  *
diff --git a/toxav/toxav.h b/toxav/toxav.h
index b0e7e37d..c75f8bff 100644
--- a/toxav/toxav.h
+++ b/toxav/toxav.h
@@ -1,22 +1,22 @@
-/**  toxav.h
+/* toxav.h
  * 
- *   Copyright (C) 2013-2015 Tox project All Rights Reserved.
+ * Copyright (C) 2013-2015 Tox project All Rights Reserved.
  *
- *   This file is part of Tox.
+ * This file is part of Tox.
  *
- *   Tox is free software: you can redistribute it and/or modify
- *   it under the terms of the GNU General Public License as published by
- *   the Free Software Foundation, either version 3 of the License, or
- *   (at your option) any later version.
+ * Tox is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- *   Tox is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *   GNU General Public License for more details.
- *
- *   You should have received a copy of the GNU General Public License
- *   along with Tox. If not, see <http://www.gnu.org/licenses/>.
+ * Tox is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
+ * You should have received a copy of the GNU General Public License
+ * along with Tox. If not, see <http://www.gnu.org/licenses/>.
+ * 
  */
 
 #ifndef TOXAV_H
@@ -29,45 +29,175 @@
 #ifdef __cplusplus
 extern "C" {
 #endif
+
 /** \page av Public audio/video API for Tox clients.
  * 
+ * This API can handle multiple calls. Each call has its state, in very rare
+ * occasions the library can change the state of the call without apps knowledge.
+ * 
+ */
+/** \subsection events Events and callbacks
+ *
+ * As in Core API, events are handled by callbacks. One callback can be 
+ * registered per event. All events have a callback function type named 
+ * `toxav_{event}_cb` and a function to register it named `tox_callback_{event}`. 
+ * Passing a NULL callback will result in no callback being registered for that 
+ * event. Only one callback per event can be registered, so if a client needs 
+ * multiple event listeners, it needs to implement the dispatch functionality 
+ * itself. Unlike Core API, lack of some event handlers will cause the the 
+ * library to drop calls before they are started. Hanging up call from a 
+ * callback causes undefined behaviour.
+ * 
+ */
+/** \subsection threading Threading implications
+ *
  * Unlike the Core API, this API is fully thread-safe. The library will ensure
- * the proper synchronisation of parallel calls.
+ * the proper synchronisation of parallel calls. 
+ * 
+ * A common way to run ToxAV (multiple or single instance) is to have a thread,
+ * separate from tox instance thread, running a simple toxav_iterate loop, 
+ * sleeping for toxav_iteration_interval * milliseconds on each iteration.
+ *
  */
 /**
- * The type of the Tox Audio/Video subsystem object.
+ * External Tox type.
  */
-typedef struct ToxAV ToxAV;
 #ifndef TOX_DEFINED
 #define TOX_DEFINED
+typedef struct Tox Tox;
+#endif /* TOX_DEFINED */
+
 /**
- * The type of a Tox instance. Repeated here so this file does not have a direct
- * dependency on the Core interface.
+ * ToxAV.
  */
-typedef struct Tox Tox;
-#endif
+/**
+ * The ToxAV instance type. Each ToxAV instance can be bound to only one Tox
+ * instance, and Tox instance can have only one ToxAV instance. One must make
+ * sure to close ToxAV instance prior closing Tox instance otherwise undefined
+ * behaviour occurs. Upon closing of ToxAV instance, all active calls will be 
+ * forcibly terminated without notifying peers.
+ * 
+ */
+#ifndef TOXAV_DEFINED
+#define TOXAV_DEFINED
+typedef struct ToxAV ToxAV;
+#endif /* TOXAV_DEFINED */
+
+
+/*******************************************************************************
+ *
+ * :: API version
+ *
+ ******************************************************************************/
+
+
+
+/**
+ * The major version number. Incremented when the API or ABI changes in an
+ * incompatible way.
+ */
+#define TOXAV_VERSION_MAJOR               0u
+
+/**
+ * The minor version number. Incremented when functionality is added without
+ * breaking the API or ABI. Set to 0 when the major version number is
+ * incremented.
+ */
+#define TOXAV_VERSION_MINOR               0u
+
+/**
+ * The patch or revision number. Incremented when bugfixes are applied without
+ * changing any functionality or API or ABI.
+ */
+#define TOXAV_VERSION_PATCH               0u
+
+/**
+ * A macro to check at preprocessing time whether the client code is compatible
+ * with the installed version of ToxAV.
+ */
+#define TOXAV_VERSION_IS_API_COMPATIBLE(MAJOR, MINOR, PATCH)        \
+  (TOXAV_VERSION_MAJOR == MAJOR &&                                \
+   (TOXAV_VERSION_MINOR > MINOR ||                                \
+    (TOXAV_VERSION_MINOR == MINOR &&                              \
+     TOXAV_VERSION_PATCH >= PATCH)))
+
+/**
+ * A macro to make compilation fail if the client code is not compatible with
+ * the installed version of ToxAV.
+ */
+#define TOXAV_VERSION_REQUIRE(MAJOR, MINOR, PATCH)                \
+  typedef char toxav_required_version[TOXAV_IS_COMPATIBLE(MAJOR, MINOR, PATCH) ? 1 : -1]
+
+/**
+ * A convenience macro to call toxav_version_is_compatible with the currently
+ * compiling API version.
+ */
+#define TOXAV_VERSION_IS_ABI_COMPATIBLE()                         \
+  toxav_version_is_compatible(TOXAV_VERSION_MAJOR, TOXAV_VERSION_MINOR, TOXAV_VERSION_PATCH)
+
+/**
+ * Return the major version number of the library. Can be used to display the
+ * ToxAV library version or to check whether the client is compatible with the
+ * dynamically linked version of ToxAV.
+ */
+uint32_t toxav_version_major(void);
+
+/**
+ * Return the minor version number of the library.
+ */
+uint32_t toxav_version_minor(void);
+
+/**
+ * Return the patch number of the library.
+ */
+uint32_t toxav_version_patch(void);
+
+/**
+ * Return whether the compiled library version is compatible with the passed
+ * version numbers.
+ */
+bool toxav_version_is_compatible(uint32_t major, uint32_t minor, uint32_t patch);
+
+
 /*******************************************************************************
  * 
  * :: Creation and destruction
  *
  ******************************************************************************/
+
+
+
 typedef enum TOXAV_ERR_NEW {
-    TOXAV_ERR_NEW_OK,
-    TOXAV_ERR_NEW_NULL,
-    /**
-     * Memory allocation failure while trying to allocate structures required for
-     * the A/V session.
-     */
-    TOXAV_ERR_NEW_MALLOC,
-    /**
-     * Attempted to create a second session for the same Tox instance.
-     */
-    TOXAV_ERR_NEW_MULTIPLE
+
+  /**
+   * The function returned successfully.
+   */
+  TOXAV_ERR_NEW_OK,
+  
+  /**
+   * One of the arguments to the function was NULL when it was not expected.
+   */
+  TOXAV_ERR_NEW_NULL,
+  
+  /**
+   * Memory allocation failure while trying to allocate structures required for
+   * the A/V session.
+   */
+  TOXAV_ERR_NEW_MALLOC,
+  
+  /**
+   * Attempted to create a second session for the same Tox instance.
+   */
+  TOXAV_ERR_NEW_MULTIPLE,
+  
 } TOXAV_ERR_NEW;
+
+
 /**
  * Start new A/V session. There can only be only one session per Tox instance.
  */
 ToxAV *toxav_new(Tox *tox, TOXAV_ERR_NEW *error);
+
 /**
  * Releases all resources associated with the A/V session.
  *
@@ -75,62 +205,86 @@ ToxAV *toxav_new(Tox *tox, TOXAV_ERR_NEW *error);
  * notifying peers. After calling this function, no other functions may be
  * called and the av pointer becomes invalid.
  */
-void toxav_kill(ToxAV *av);
+void toxav_kill(ToxAV *toxAV);
+
 /**
  * Returns the Tox instance the A/V object was created for.
  */
-Tox *toxav_get_tox(ToxAV *av);
+Tox *toxav_get_tox(const ToxAV *toxAV);
+
+
 /*******************************************************************************
  * 
  * :: A/V event loop
  *
  ******************************************************************************/
+
+
+
 /**
  * Returns the interval in milliseconds when the next toxav_iterate call should
  * be. If no call is active at the moment, this function returns 200.
  */
-uint32_t toxav_iteration_interval(ToxAV const *av);
+uint32_t toxav_iteration_interval(const ToxAV *toxAV);
+
 /**
  * Main loop for the session. This function needs to be called in intervals of
  * toxav_iteration_interval() milliseconds. It is best called in the separate 
  * thread from tox_iterate.
  */
-void toxav_iterate(ToxAV *av);
+void toxav_iterate(ToxAV *toxAV);
+
+
 /*******************************************************************************
  * 
  * :: Call setup
  *
  ******************************************************************************/
+
+
+
 typedef enum TOXAV_ERR_CALL {
-    TOXAV_ERR_CALL_OK,
-    /**
-     * A resource allocation error occurred while trying to create the structures
-     * required for the call.
-     */
-    TOXAV_ERR_CALL_MALLOC,
-    /**
-     * The friend number did not designate a valid friend.
-     */
-    TOXAV_ERR_CALL_FRIEND_NOT_FOUND,
-    /**
-     * The friend was valid, but not currently connected.
-     */
-    TOXAV_ERR_CALL_FRIEND_NOT_CONNECTED,
-    /**
-     * Attempted to call a friend while already in an audio or video call with
-     * them.
-     */
-    TOXAV_ERR_CALL_FRIEND_ALREADY_IN_CALL,
-    /**
-     * Audio or video bit rate is invalid.
-     */
-    TOXAV_ERR_CALL_INVALID_BIT_RATE
+
+  /**
+   * The function returned successfully.
+   */
+  TOXAV_ERR_CALL_OK,
+  
+  /**
+   * A resource allocation error occurred while trying to create the structures
+   * required for the call.
+   */
+  TOXAV_ERR_CALL_MALLOC,
+  
+  /**
+   * The friend number did not designate a valid friend.
+   */
+  TOXAV_ERR_CALL_FRIEND_NOT_FOUND,
+  
+  /**
+   * The friend was valid, but not currently connected.
+   */
+  TOXAV_ERR_CALL_FRIEND_NOT_CONNECTED,
+  
+  /**
+   * Attempted to call a friend while already in an audio or video call with
+   * them.
+   */
+  TOXAV_ERR_CALL_FRIEND_ALREADY_IN_CALL,
+  
+  /**
+   * Audio or video bit rate is invalid.
+   */
+  TOXAV_ERR_CALL_INVALID_BIT_RATE,
+  
 } TOXAV_ERR_CALL;
+
+
 /**
  * Call a friend. This will start ringing the friend.
  *
  * It is the client's responsibility to stop ringing after a certain timeout,
- * if such behaviour is desired. If the client does not stop ringing, the A/V
+ * if such behaviour is desired. If the client does not stop ringing, the
  * library will not stop until the friend is disconnected.
  *
  * @param friend_number The friend number of the friend that should be called.
@@ -139,39 +293,57 @@ typedef enum TOXAV_ERR_CALL {
  * @param video_bit_rate Video bit rate in Kb/sec. Set this to 0 to disable
  * video sending.
  */
-bool toxav_call(ToxAV *av, uint32_t friend_number, uint32_t audio_bit_rate, uint32_t video_bit_rate, TOXAV_ERR_CALL *error);
+bool toxav_call(ToxAV *toxAV, uint32_t friend_number, uint32_t audio_bit_rate, uint32_t video_bit_rate, TOXAV_ERR_CALL *error);
+
 /**
- * The function type for the `call` callback.
+ * The function type for the call callback.
+ * 
+ * @param friend_number The friend number from which the call is incoming.
+ * @param audio_enabled True if friend is sending audio.
+ * @param video_enabled True if friend is sending video.
  */
-typedef void toxav_call_cb(ToxAV *av, uint32_t friend_number, bool audio_enabled, bool video_enabled, void *user_data);
+typedef void toxav_call_cb(ToxAV *toxAV, uint32_t friend_number, bool audio_enabled, bool video_enabled, void *user_data);
+
+
 /**
  * Set the callback for the `call` event. Pass NULL to unset.
  *
- * This event is triggered when a call is received from a friend.
  */
-void toxav_callback_call(ToxAV *av, toxav_call_cb *function, void *user_data);
+void toxav_callback_call(ToxAV *toxAV, toxav_call_cb *callback, void *user_data);
+
 typedef enum TOXAV_ERR_ANSWER {
-    TOXAV_ERR_ANSWER_OK,
-    /**
-     * Failed to initialize codecs for call session. Note that codec initiation
-     * will fail if there is no receive callback registered for either audio or
-     * video.
-     */
-    TOXAV_ERR_ANSWER_CODEC_INITIALIZATION,
-    /**
-     * The friend number did not designate a valid friend.
-     */
-    TOXAV_ERR_ANSWER_FRIEND_NOT_FOUND,
-    /**
-     * The friend was valid, but they are not currently trying to initiate a call.
-     * This is also returned if this client is already in a call with the friend.
-     */
-    TOXAV_ERR_ANSWER_FRIEND_NOT_CALLING,
-    /**
-     * Audio or video bit rate is invalid.
-     */
-    TOXAV_ERR_ANSWER_INVALID_BIT_RATE
+
+  /**
+   * The function returned successfully.
+   */
+  TOXAV_ERR_ANSWER_OK,
+  
+  /**
+   * Failed to initialize codecs for call session. Note that codec initiation
+   * will fail if there is no receive callback registered for either audio or
+   * video.
+   */
+  TOXAV_ERR_ANSWER_CODEC_INITIALIZATION,
+  
+  /**
+   * The friend number did not designate a valid friend.
+   */
+  TOXAV_ERR_ANSWER_FRIEND_NOT_FOUND,
+  
+  /**
+   * The friend was valid, but they are not currently trying to initiate a call.
+   * This is also returned if this client is already in a call with the friend.
+   */
+  TOXAV_ERR_ANSWER_FRIEND_NOT_CALLING,
+  
+  /**
+   * Audio or video bit rate is invalid.
+   */
+  TOXAV_ERR_ANSWER_INVALID_BIT_RATE,
+  
 } TOXAV_ERR_ANSWER;
+
+
 /**
  * Accept an incoming call.
  *
@@ -184,113 +356,155 @@ typedef enum TOXAV_ERR_ANSWER {
  * @param video_bit_rate Video bit rate in Kb/sec. Set this to 0 to disable
  * video sending.
  */
-bool toxav_answer(ToxAV *av, uint32_t friend_number, uint32_t audio_bit_rate, uint32_t video_bit_rate, TOXAV_ERR_ANSWER *error);
+bool toxav_answer(ToxAV *toxAV, uint32_t friend_number, uint32_t audio_bit_rate, uint32_t video_bit_rate, TOXAV_ERR_ANSWER *error);
+
+
 /*******************************************************************************
  * 
  * :: Call state graph
  *
  ******************************************************************************/
+
+
+
 enum TOXAV_CALL_STATE {
-    /**
-     * The flag that marks that friend is sending audio.
-     */
-    TOXAV_CALL_STATE_SENDING_A = 1,
-    /**
-     * The flag that marks that friend is sending video.
-     */
-    TOXAV_CALL_STATE_SENDING_V = 2,
-    /**
-     * The flag that marks that friend is receiving audio.
-     */
-    TOXAV_CALL_STATE_RECEIVING_A = 4,
-    /**
-     * The flag that marks that friend is receiving video.
-     */
-    TOXAV_CALL_STATE_RECEIVING_V = 8,
-    /**
-     * The call has finished. This is the final state after which no more state
-     * transitions can occur for the call. This call state will never be 
-     * triggered in combination with other call states.
-     */
-    TOXAV_CALL_STATE_FINISHED = 16,
-    /**
-     * Set by the AV core if an error occurred on the remote end. This call 
-     * state will never be triggered in combination with other call states.
-     */
-    TOXAV_CALL_STATE_ERROR = 32768
+
+  /**
+   * Set by the AV core if an error occurred on the remote end or if friend 
+   * timed out. This is the final state after which no more state
+   * transitions can occur for the call. This call state will never be triggered
+   * in combination with other call states.
+   */
+  TOXAV_CALL_STATE_ERROR = 1,
+  
+  /**
+   * The call has finished. This is the final state after which no more state
+   * transitions can occur for the call. This call state will never be 
+   * triggered in combination with other call states.
+   */
+  TOXAV_CALL_STATE_FINISHED = 2,
+  
+  /**
+   * The flag that marks that friend is sending audio.
+   */
+  TOXAV_CALL_STATE_SENDING_A = 4,
+  
+  /**
+   * The flag that marks that friend is sending video.
+   */
+  TOXAV_CALL_STATE_SENDING_V = 8,
+  
+  /**
+   * The flag that marks that friend is receiving audio.
+   */
+  TOXAV_CALL_STATE_RECEIVING_A = 16,
+  
+  /**
+   * The flag that marks that friend is receiving video.
+   */
+  TOXAV_CALL_STATE_RECEIVING_V = 32,
+  
 };
+
+
 /**
- * The function type for the `call_state` callback.
+ * The function type for the call_state callback.
  *
  * @param friend_number The friend number for which the call state changed.
- * @param state The new call state.
+ * @param state The new call state which is guaranteed to be different than 
+ * the previous state. The state is set to 0 when the call is paused.
  */
-typedef void toxav_call_state_cb(ToxAV *av, uint32_t friend_number, uint32_t state, void *user_data);
+typedef void toxav_call_state_cb(ToxAV *toxAV, uint32_t friend_number, uint32_t state, void *user_data);
+
+
 /**
  * Set the callback for the `call_state` event. Pass NULL to unset.
  *
- * This event is triggered when a call state transition occurs.
  */
-void toxav_callback_call_state(ToxAV *av, toxav_call_state_cb *function, void *user_data);
+void toxav_callback_call_state(ToxAV *toxAV, toxav_call_state_cb *callback, void *user_data);
+
+
 /*******************************************************************************
  * 
  * :: Call control
  *
  ******************************************************************************/
+
+
+
 typedef enum TOXAV_CALL_CONTROL {
-    /**
-     * Resume a previously paused call. Only valid if the pause was caused by this
-     * client, if not, this control is ignored. Not valid before the call is accepted.
-     */
-    TOXAV_CALL_CONTROL_RESUME,
-    /**
-     * Put a call on hold. Not valid before the call is accepted.
-     */
-    TOXAV_CALL_CONTROL_PAUSE,
-    /**
-     * Reject a call if it was not answered, yet. Cancel a call after it was
-     * answered.
-     */
-    TOXAV_CALL_CONTROL_CANCEL,
-    /**
-     * Request that the friend stops sending audio. Regardless of the friend's
-     * compliance, this will cause the `receive_audio_frame` event to stop being
-     * triggered on receiving an audio frame from the friend. If the audio was
-     * already muted, calling this control will notify client to start sending
-     * audio again.
-     */
-    TOXAV_CALL_CONTROL_TOGGLE_MUTE_AUDIO,
-    /**
-     * Request that the friend stops sending video. Regardless of the friend's
-     * compliance, this will cause the `receive_video_frame` event to stop being
-     * triggered on receiving an video frame from the friend. If the video was
-     * already hidden, calling this control will notify client to start sending
-     * video again.
-     */
-    TOXAV_CALL_CONTROL_TOGGLE_HIDE_VIDEO
+
+  /**
+   * Resume a previously paused call. Only valid if the pause was caused by this
+   * client, if not, this control is ignored. Not valid before the call is accepted.
+   */
+  TOXAV_CALL_CONTROL_RESUME,
+  
+  /**
+   * Put a call on hold. Not valid before the call is accepted.
+   */
+  TOXAV_CALL_CONTROL_PAUSE,
+  
+  /**
+   * Reject a call if it was not answered, yet. Cancel a call after it was
+   * answered.
+   */
+  TOXAV_CALL_CONTROL_CANCEL,
+  
+  /**
+   * Request that the friend stops sending audio. Regardless of the friend's
+   * compliance, this will cause the audio_receive_frame event to stop being
+   * triggered on receiving an audio frame from the friend.
+   */
+  TOXAV_CALL_CONTROL_MUTE_AUDIO,
+  
+  /**
+   * Calling this control will notify client to start sending audio again.
+   */
+  TOXAV_CALL_CONTROL_UNMUTE_AUDIO,
+  
+  /**
+   * Request that the friend stops sending video. Regardless of the friend's
+   * compliance, this will cause the video_receive_frame event to stop being
+   * triggered on receiving an video frame from the friend.
+   */
+  TOXAV_CALL_CONTROL_HIDE_VIDEO,
+  
+  /**
+   * Calling this control will notify client to start sending video again.
+   */
+  TOXAV_CALL_CONTROL_SHOW_VIDEO,
+  
 } TOXAV_CALL_CONTROL;
+
+
 typedef enum TOXAV_ERR_CALL_CONTROL {
-    TOXAV_ERR_CALL_CONTROL_OK,
-    /**
-     * The friend_number passed did not designate a valid friend.
-     */
-    TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_FOUND,
-    /**
-     * This client is currently not in a call with the friend. Before the call is
-     * answered, only CANCEL is a valid control.
-     */
-    TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_IN_CALL,
-    /**
-     * Attempted to resume a call that was not paused.
-     */
-    TOXAV_ERR_CALL_CONTROL_NOT_PAUSED,
-    /**
-     * The call was already paused on this client. It is valid to pause if the
-     * other party paused the call. The call will resume after both parties sent
-     * the RESUME control.
-     */
-    TOXAV_ERR_CALL_CONTROL_ALREADY_PAUSED
+
+  /**
+   * The function returned successfully.
+   */
+  TOXAV_ERR_CALL_CONTROL_OK,
+  
+  /**
+   * The friend_number passed did not designate a valid friend.
+   */
+  TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_FOUND,
+  
+  /**
+   * This client is currently not in a call with the friend. Before the call is
+   * answered, only CANCEL is a valid control.
+   */
+  TOXAV_ERR_CALL_CONTROL_FRIEND_NOT_IN_CALL,
+  
+  /**
+   * Happens if user tried to pause an already paused call or if trying to
+   * resume a call that is not paused.
+   */
+  TOXAV_ERR_CALL_CONTROL_INVALID_TRANSITION,
+  
 } TOXAV_ERR_CALL_CONTROL;
+
+
 /**
  * Sends a call control command to a friend.
  *
@@ -300,29 +514,44 @@ typedef enum TOXAV_ERR_CALL_CONTROL {
  *
  * @return true on success.
  */
-bool toxav_call_control(ToxAV *av, uint32_t friend_number, TOXAV_CALL_CONTROL control, TOXAV_ERR_CALL_CONTROL *error);
+bool toxav_call_control(ToxAV *toxAV, uint32_t friend_number, TOXAV_CALL_CONTROL control, TOXAV_ERR_CALL_CONTROL *error);
+
+
 /*******************************************************************************
  * 
  * :: Controlling bit rates
  *
  ******************************************************************************/
-typedef enum TOXAV_ERR_BIT_RATE {
-    TOXAV_ERR_BIT_RATE_OK,
-    /**
-     * The bit rate passed was not one of the supported values.
-     */
-    TOXAV_ERR_BIT_RATE_INVALID,
-    /**
-     * The friend_number passed did not designate a valid friend.
-     */
-    TOXAV_ERR_BIT_RATE_FRIEND_NOT_FOUND,
-    /**
-     * This client is currently not in a call with the friend.
-     */
-    TOXAV_ERR_BIT_RATE_FRIEND_NOT_IN_CALL
-} TOXAV_ERR_BIT_RATE;
-/**
- * The function type for the `audio_bit_rate_status` callback.
+
+
+
+typedef enum TOXAV_ERR_SET_BIT_RATE {
+
+  /**
+   * The function returned successfully.
+   */
+  TOXAV_ERR_SET_BIT_RATE_OK,
+  
+  /**
+   * The bit rate passed was not one of the supported values.
+   */
+  TOXAV_ERR_SET_BIT_RATE_INVALID,
+  
+  /**
+   * The friend_number passed did not designate a valid friend.
+   */
+  TOXAV_ERR_SET_BIT_RATE_FRIEND_NOT_FOUND,
+  
+  /**
+   * This client is currently not in a call with the friend.
+   */
+  TOXAV_ERR_SET_BIT_RATE_FRIEND_NOT_IN_CALL,
+  
+} TOXAV_ERR_SET_BIT_RATE;
+
+
+/**
+ * The function type for the audio_bit_rate_status callback.
  * 
  * @param friend_number The friend number of the friend for which to set the
  * audio bit rate.
@@ -334,11 +563,15 @@ typedef enum TOXAV_ERR_BIT_RATE {
  * or the non forceful change failed.
  * @param bit_rate The bit rate in Kb/sec.
  */
-typedef void toxav_audio_bit_rate_status_cb(ToxAV *av, uint32_t friend_number, bool stable, uint32_t bit_rate, void *user_data);
+typedef void toxav_audio_bit_rate_status_cb(ToxAV *toxAV, uint32_t friend_number, bool stable, uint32_t bit_rate, void *user_data);
+
+
 /**
  * Set the callback for the `audio_bit_rate_status` event. Pass NULL to unset.
+ *
  */
-void toxav_callback_audio_bit_rate_status(ToxAV *av, toxav_audio_bit_rate_status_cb *function, void *user_data);
+void toxav_callback_audio_bit_rate_status(ToxAV *toxAV, toxav_audio_bit_rate_status_cb *callback, void *user_data);
+
 /**
  * Set the audio bit rate to be used in subsequent audio frames. If the passed 
  * bit rate is the same as the current bit rate this function will return true 
@@ -351,12 +584,13 @@ void toxav_callback_audio_bit_rate_status(ToxAV *av, toxav_audio_bit_rate_status
  * audio bit rate.
  * @param audio_bit_rate The new audio bit rate in Kb/sec. Set to 0 to disable
  * audio sending.
- *
- * @see toxav_call for the valid bit rates.
+ * @param force True if the bit rate change is forceful.
+ * 
  */
-bool toxav_set_audio_bit_rate(ToxAV *av, uint32_t friend_number, uint32_t audio_bit_rate, bool force, TOXAV_ERR_BIT_RATE *error);
+bool toxav_audio_bit_rate_set(ToxAV *toxAV, uint32_t friend_number, uint32_t audio_bit_rate, bool force, TOXAV_ERR_SET_BIT_RATE *error);
+
 /**
- * The function type for the `video_bit_rate_status` callback.
+ * The function type for the video_bit_rate_status callback.
  * 
  * @param friend_number The friend number of the friend for which to set the
  * video bit rate.
@@ -368,79 +602,78 @@ bool toxav_set_audio_bit_rate(ToxAV *av, uint32_t friend_number, uint32_t audio_
  * or the non forceful change failed.
  * @param bit_rate The bit rate in Kb/sec.
  */
-typedef void toxav_video_bit_rate_status_cb(ToxAV *av, uint32_t friend_number, bool stable, uint32_t bit_rate, void *user_data);
+typedef void toxav_video_bit_rate_status_cb(ToxAV *toxAV, uint32_t friend_number, bool stable, uint32_t bit_rate, void *user_data);
+
+
 /**
  * Set the callback for the `video_bit_rate_status` event. Pass NULL to unset.
+ *
  */
-void toxav_callback_video_bit_rate_status(ToxAV *av, toxav_video_bit_rate_status_cb *function, void *user_data);
+void toxav_callback_video_bit_rate_status(ToxAV *toxAV, toxav_video_bit_rate_status_cb *callback, void *user_data);
+
 /**
  * Set the video bit rate to be used in subsequent video frames. If the passed 
  * bit rate is the same as the current bit rate this function will return true 
  * without calling a callback. If there is an active non forceful setup with the
- * passed bit rate and the new set request is forceful, the bit rate is 
+ * passed video bit rate and the new set request is forceful, the bit rate is 
  * forcefully set and the previous non forceful request is cancelled. The active
  * non forceful setup will be canceled in favour of new non forceful setup.
  *
  * @param friend_number The friend number of the friend for which to set the
  * video bit rate.
- * @param video_bit_rate The new video bit rate in Kb/sec. Set to 0 to disable
+ * @param audio_bit_rate The new video bit rate in Kb/sec. Set to 0 to disable
  * video sending.
- *
- * @see toxav_call for the valid bit rates.
+ * @param force True if the bit rate change is forceful.
+ * 
  */
-bool toxav_set_video_bit_rate(ToxAV *av, uint32_t friend_number, uint32_t video_bit_rate, bool force, TOXAV_ERR_BIT_RATE *error);
+bool toxav_video_bit_rate_set(ToxAV *toxAV, uint32_t friend_number, uint32_t audio_bit_rate, bool force, TOXAV_ERR_SET_BIT_RATE *error);
+
+
 /*******************************************************************************
  * 
  * :: A/V sending
  *
  ******************************************************************************/
-/**
- * Common error codes for the send_*_frame functions.
- */
+
+
+
 typedef enum TOXAV_ERR_SEND_FRAME {
-    TOXAV_ERR_SEND_FRAME_OK,
-    /**
-     * In case of video, one of Y, U, or V was NULL. In case of audio, the samples
-     * data pointer was NULL.
-     */
-    TOXAV_ERR_SEND_FRAME_NULL,
-    /**
-     * The friend_number passed did not designate a valid friend.
-     */
-    TOXAV_ERR_SEND_FRAME_FRIEND_NOT_FOUND,
-    /**
-     * This client is currently not in a call with the friend.
-     */
-    TOXAV_ERR_SEND_FRAME_FRIEND_NOT_IN_CALL,
-    /**
-     * One of the frame parameters was invalid. E.g. the resolution may be too
-     * small or too large, or the audio sampling rate may be unsupported.
-     */
-    TOXAV_ERR_SEND_FRAME_INVALID,
-        /**
-     * Failed to push frame through rtp interface.
-     */
-        TOXAV_ERR_SEND_FRAME_RTP_FAILED
+
+  /**
+   * The function returned successfully.
+   */
+  TOXAV_ERR_SEND_FRAME_OK,
+  
+  /**
+   * In case of video, one of Y, U, or V was NULL. In case of audio, the samples
+   * data pointer was NULL.
+   */
+  TOXAV_ERR_SEND_FRAME_NULL,
+  
+  /**
+   * The friend_number passed did not designate a valid friend.
+   */
+  TOXAV_ERR_SEND_FRAME_FRIEND_NOT_FOUND,
+  
+  /**
+   * This client is currently not in a call with the friend.
+   */
+  TOXAV_ERR_SEND_FRAME_FRIEND_NOT_IN_CALL,
+  
+  /**
+   * One of the frame parameters was invalid. E.g. the resolution may be too
+   * small or too large, or the audio sampling rate may be unsupported.
+   */
+  TOXAV_ERR_SEND_FRAME_INVALID,
+  
+  /**
+   * Failed to push frame through rtp interface.
+   */
+  TOXAV_ERR_SEND_FRAME_RTP_FAILED,
+  
 } TOXAV_ERR_SEND_FRAME;
-/**
- * Send a video frame to a friend.
- *
- * Y - plane should be of size: height * width
- * U - plane should be of size: (height/2) * (width/2)
- * V - plane should be of size: (height/2) * (width/2)
- *
- * @param friend_number The friend number of the friend to which to send a video
- * frame.
- * @param width Width of the frame in pixels.
- * @param height Height of the frame in pixels.
- * @param y Y (Luminance) plane data.
- * @param u U (Chroma) plane data.
- * @param v V (Chroma) plane data.
- */
-bool toxav_send_video_frame(ToxAV *av, uint32_t friend_number,
-                            uint16_t width, uint16_t height,
-                            uint8_t const *y, uint8_t const *u, uint8_t const *v,
-                            TOXAV_ERR_SEND_FRAME *error);
+
+
 /**
  * Send an audio frame to a friend.
  *
@@ -461,19 +694,56 @@ bool toxav_send_video_frame(ToxAV *av, uint32_t friend_number,
  * @param sampling_rate Audio sampling rate used in this frame. Valid sampling
  * rates are 8000, 12000, 16000, 24000, or 48000.
  */
-bool toxav_send_audio_frame(ToxAV *av, uint32_t friend_number,
-                            int16_t const *pcm,
-                            size_t sample_count,
-                            uint8_t channels,
-                            uint32_t sampling_rate,
-                            TOXAV_ERR_SEND_FRAME *error);
+bool toxav_audio_send_frame(ToxAV *toxAV, uint32_t friend_number, const int16_t *pcm, size_t sample_count, uint8_t channels, uint32_t sampling_rate, TOXAV_ERR_SEND_FRAME *error);
+
+/**
+ * Send a video frame to a friend.
+ *
+ * Y - plane should be of size: height * width
+ * U - plane should be of size: (height/2) * (width/2)
+ * V - plane should be of size: (height/2) * (width/2)
+ *
+ * @param friend_number The friend number of the friend to which to send a video
+ * frame.
+ * @param width Width of the frame in pixels.
+ * @param height Height of the frame in pixels.
+ * @param y Y (Luminance) plane data.
+ * @param u U (Chroma) plane data.
+ * @param v V (Chroma) plane data.
+ * @param a A (Alpha) plane data.
+ */
+bool toxav_video_send_frame(ToxAV *toxAV, uint32_t friend_number, uint16_t width, uint16_t height, const uint8_t *y, const uint8_t *u, const uint8_t *v, const uint8_t *a, TOXAV_ERR_SEND_FRAME *error);
+
+
 /*******************************************************************************
  * 
  * :: A/V receiving
  *
  ******************************************************************************/
+
+
+
 /**
- * The function type for the `receive_video_frame` callback.
+ * The function type for the audio_receive_frame callback.
+ *
+ * @param friend_number The friend number of the friend who sent an audio frame.
+ * @param pcm An array of audio samples (sample_count * channels elements).
+ * @param sample_count The number of audio samples per channel in the PCM array.
+ * @param channels Number of audio channels.
+ * @param sampling_rate Sampling rate used in this frame.
+ *
+ */
+typedef void toxav_audio_receive_frame_cb(ToxAV *toxAV, uint32_t friend_number, const int16_t *pcm, size_t sample_count, uint8_t channels, uint32_t sampling_rate, void *user_data);
+
+
+/**
+ * Set the callback for the `audio_receive_frame` event. Pass NULL to unset.
+ *
+ */
+void toxav_callback_audio_receive_frame(ToxAV *toxAV, toxav_audio_receive_frame_cb *callback, void *user_data);
+
+/**
+ * The function type for the video_receive_frame callback.
  *
  * @param friend_number The friend number of the friend who sent a video frame.
  * @param width Width of the frame in pixels.
@@ -482,44 +752,26 @@ bool toxav_send_audio_frame(ToxAV *av, uint32_t friend_number,
  * @param u 
  * @param v Plane data.
  *          The size of plane data is derived from width and height where
- *          Y = width * height, U = (width/2) * (height/2) and V = (width/2) * (height/2).
+ *          Y = MAX(width, abs(ystride)) * height, 
+ *          U = MAX(width/2, abs(ustride)) * (height/2) and 
+ *          V = MAX(width/2, abs(vstride)) * (height/2).
+ *          A = MAX(width, abs(astride)) * height.
  * @param ystride
  * @param ustride
- * @param vstride Strides data.
- */
-typedef void toxav_receive_video_frame_cb(ToxAV *av, uint32_t friend_number,
-                                          uint16_t width, uint16_t height,
-                                          uint8_t const *y, uint8_t const *u, uint8_t const *v, 
-                                          int32_t ystride, int32_t ustride, int32_t vstride,
-                                          void *user_data);
-/**
- * Set the callback for the `receive_video_frame` event. Pass NULL to unset.
+ * @param vstride
+ * @param astride Strides data. Strides represent padding for each plane
+ *                that may or may not be present. You must handle strides in
+ *                your image processing code. Strides are negative if the 
+ *                image is bottom-up hence why you MUST abs() it when
+ *                calculating plane buffer size.
  */
-void toxav_callback_receive_video_frame(ToxAV *av, toxav_receive_video_frame_cb *function, void *user_data);
+typedef void toxav_video_receive_frame_cb(ToxAV *toxAV, uint32_t friend_number, uint16_t width, uint16_t height, const uint8_t *y, const uint8_t *u, const uint8_t *v, const uint8_t *a, int32_t ystride, int32_t ustride, int32_t vstride, int32_t astride, void *user_data);
+
+
 /**
- * The function type for the `receive_audio_frame` callback.
- *
- * @param friend_number The friend number of the friend who sent an audio frame.
- * @param pcm An array of audio samples (sample_count * channels elements).
- * @param sample_count The number of audio samples per channel in the PCM array.
- * @param channels Number of audio channels.
- * @param sampling_rate Sampling rate used in this frame.
+ * Set the callback for the `video_receive_frame` event. Pass NULL to unset.
  *
- * @see toxav_send_audio_frame for the audio format.
- */
-typedef void toxav_receive_audio_frame_cb(ToxAV *av, uint32_t friend_number,
-                                          int16_t const *pcm,
-                                          size_t sample_count,
-                                          uint8_t channels,
-                                          uint32_t sampling_rate,
-                                          void *user_data);
-/**
- * Set the callback for the `receive_audio_frame` event. Pass NULL to unset.
  */
-void toxav_callback_receive_audio_frame(ToxAV *av, toxav_receive_audio_frame_cb *function, void *user_data);
+void toxav_callback_video_receive_frame(ToxAV *toxAV, toxav_video_receive_frame_cb *callback, void *user_data);
 
-#ifdef __cplusplus
-}
 #endif
-
-#endif /* TOXAV_H */
diff --git a/toxav/video.c b/toxav/video.c
index fe57387f..690b3bd4 100644
--- a/toxav/video.c
+++ b/toxav/video.c
@@ -42,7 +42,7 @@ typedef struct { uint16_t size; uint8_t data[]; } Payload;
 bool create_video_encoder (vpx_codec_ctx_t* dest, int32_t bit_rate);
 
 
-VCSession* vc_new(ToxAV* av, uint32_t friend_number, toxav_receive_video_frame_cb* cb, void* cb_data, uint32_t mvfpsz)
+VCSession* vc_new(ToxAV* av, uint32_t friend_number, toxav_video_receive_frame_cb* cb, void* cb_data, uint32_t mvfpsz)
 {
     VCSession *vc = calloc(sizeof(VCSession), 1);
     
@@ -141,8 +141,9 @@ void vc_do(VCSession* vc)
             for (; dest; dest = vpx_codec_get_frame(vc->decoder, &iter)) {
                 if (vc->vcb.first) 
                     vc->vcb.first(vc->av, vc->friend_number, dest->d_w, dest->d_h, 
-                                  (const uint8_t*)dest->planes[0], (const uint8_t*)dest->planes[1], (const uint8_t*)dest->planes[2],
-                                  dest->stride[0], dest->stride[1], dest->stride[2], vc->vcb.second);
+                                  (const uint8_t*)dest->planes[0], (const uint8_t*)dest->planes[1], 
+                                  (const uint8_t*)dest->planes[2], (const uint8_t*)dest->planes[3],
+                                  dest->stride[0], dest->stride[1], dest->stride[2], dest->stride[3], vc->vcb.second);
                 
                 vpx_img_free(dest);
             }
diff --git a/toxav/video.h b/toxav/video.h
index 8da15578..96d3205d 100644
--- a/toxav/video.h
+++ b/toxav/video.h
@@ -71,7 +71,7 @@ typedef struct VCSession_s {
     ToxAV *av;
     uint32_t friend_number;
     
-    PAIR(toxav_receive_video_frame_cb *, void *) vcb; /* Video frame receive callback */
+    PAIR(toxav_video_receive_frame_cb *, void *) vcb; /* Video frame receive callback */
     
     pthread_mutex_t queue_mutex[1];
 } VCSession;
@@ -79,7 +79,7 @@ typedef struct VCSession_s {
 /*
  * Create new Video Codec session.
  */
-VCSession* vc_new(ToxAV* av, uint32_t friend_number, toxav_receive_video_frame_cb *cb, void *cb_data, uint32_t mvfpsz);
+VCSession* vc_new(ToxAV* av, uint32_t friend_number, toxav_video_receive_frame_cb *cb, void *cb_data, uint32_t mvfpsz);
 /*
  * Kill the Video Codec session.
  */