Improve playback of videos in low performance scenarios

6 files changed, 55 insertions, 55 deletions

diff --git a/include/kitchensink/internal/kitdecoder.h b/include/kitchensink/internal/kitdecoder.h
index ef3edb7..74134b0 100644
--- a/include/kitchensink/internal/kitdecoder.h
+++ b/include/kitchensink/internal/kitdecoder.h
@@ -70,6 +70,7 @@ KIT_LOCAL void Kit_ForEachDecoderOutput(Kit_Decoder *dec, Kit_ForEachItemCallbac
 KIT_LOCAL int Kit_LockDecoderOutput(Kit_Decoder *dec);

 KIT_LOCAL void Kit_UnlockDecoderOutput(Kit_Decoder *dec);

 KIT_LOCAL void Kit_ClearDecoderOutput(Kit_Decoder *dec);

+KIT_LOCAL unsigned int Kit_GetDecoderOutputLength(Kit_Decoder *dec);

 

 

 #endif // KITDECODER_H

diff --git a/include/kitchensink/internal/utils/kitbuffer.h b/include/kitchensink/internal/utils/kitbuffer.h
index 67d93c3..95d75b5 100644
--- a/include/kitchensink/internal/utils/kitbuffer.h
+++ b/include/kitchensink/internal/utils/kitbuffer.h
@@ -19,6 +19,7 @@ struct Kit_Buffer {
 KIT_LOCAL Kit_Buffer* Kit_CreateBuffer(unsigned int size, Kit_BufferFreeCallback free_cb);
 KIT_LOCAL void Kit_DestroyBuffer(Kit_Buffer *buffer);
 
+KIT_LOCAL unsigned int Kit_GetBufferLength(const Kit_Buffer *buffer);
 KIT_LOCAL void Kit_ClearBuffer(Kit_Buffer *buffer);
 KIT_LOCAL void* Kit_ReadBuffer(Kit_Buffer *buffer);
 KIT_LOCAL void* Kit_PeekBuffer(const Kit_Buffer *buffer);
diff --git a/src/internal/audio/kitaudio.c b/src/internal/audio/kitaudio.c
index e0302ee..eed1c97 100644
--- a/src/internal/audio/kitaudio.c
+++ b/src/internal/audio/kitaudio.c
@@ -276,39 +276,30 @@ int Kit_GetAudioDecoderData(Kit_Decoder *dec, unsigned char *buf, int len) {
     assert(dec != NULL);

 

     Kit_AudioPacket *next_packet = NULL;

-    Kit_AudioPacket *packet = Kit_PeekDecoderOutput(dec);

+    Kit_AudioPacket *packet = NULL;

+    int ret = 0;

+    int bytes_per_sample = 0;

+    double bytes_per_second = 0;

+    double sync_ts = 0;

+

+    // First, peek the next packet. Make sure we have something to read.

+    packet = next_packet = Kit_PeekDecoderOutput(dec);

     if(packet == NULL) {

         return 0;

     }

 

-    int ret = 0;

-    int bytes_per_sample = dec->output.bytes * dec->output.channels;

-    double bytes_per_second = bytes_per_sample * dec->output.samplerate;

-    double sync_ts = _GetSystemTime() - dec->clock_sync;

-

+    // If packet should not yet be played, stop here and wait.

+    // If packet should have already been played, skip it and try to find a better packet.

+    // For audio, it is possible that we cannot find good packet. Then just don't read anything.

+    sync_ts = _GetSystemTime() - dec->clock_sync;

     if(packet->pts > sync_ts + KIT_AUDIO_SYNC_THRESHOLD) {

         return 0;

-    } else if(packet->pts < sync_ts - KIT_AUDIO_SYNC_THRESHOLD) {

-        // Audio is lagging, skip until good pts is found

+    }

+    while(packet != NULL && packet->pts < sync_ts - KIT_AUDIO_SYNC_THRESHOLD) {

         Kit_AdvanceDecoderOutput(dec);

-        while(1) {

-            next_packet = Kit_ReadDecoderOutput(dec);

-

-            // If next packet is valid, remove this one and jump to next.

-            if(next_packet != NULL) {

-                Kit_AdvanceDecoderOutput(dec);

-                free_out_audio_packet_cb(packet);

-                packet = next_packet;

-            }

-

-            dec->clock_pos = packet->pts;

-            if(packet->pts > sync_ts - KIT_AUDIO_SYNC_THRESHOLD) {

-                break;

-            }

-        }

+        free_out_audio_packet_cb(packet);

+        packet = Kit_PeekDecoderOutput(dec);

     }

-

-    // If we have no viable packet, just skip

     if(packet == NULL) {

         return 0;

     }

@@ -316,18 +307,19 @@ int Kit_GetAudioDecoderData(Kit_Decoder *dec, unsigned char *buf, int len) {
     // Read data from packet ringbuffer

     if(len > 0) {

         ret = Kit_ReadRingBuffer(packet->rb, (char*)buf, len);

+        if(ret) {

+            bytes_per_sample = dec->output.bytes * dec->output.channels;

+            bytes_per_second = bytes_per_sample * dec->output.samplerate;

+            packet->pts += ((double)ret) / bytes_per_second;

+        }

     }

+    dec->clock_pos = packet->pts;

 

     // If ringbuffer is cleared, kill packet and advance buffer.

     // Otherwise forward the pts value for the current packet.

     if(Kit_GetRingBufferLength(packet->rb) == 0) {

         Kit_AdvanceDecoderOutput(dec);

-        dec->clock_pos = packet->pts;

         free_out_audio_packet_cb(packet);

-    } else {

-        packet->pts += ((double)ret) / bytes_per_second;

-        dec->clock_pos = packet->pts;

     }

-

     return ret;

 }

diff --git a/src/internal/kitdecoder.c b/src/internal/kitdecoder.c
index 14d2e7c..ec95621 100644
--- a/src/internal/kitdecoder.c
+++ b/src/internal/kitdecoder.c
@@ -75,7 +75,7 @@ Kit_Decoder* Kit_CreateDecoder(const Kit_Source *src, int stream_index,
 

     // Set thread count

     codec_ctx->thread_count = thread_count;

-    codec_ctx->thread_type = FF_THREAD_SLICE;

+    codec_ctx->thread_type = FF_THREAD_SLICE|FF_THREAD_FRAME;

 

     // This is required for ass_process_chunk() support

     if(LIBAVCODEC_VERSION_INT >= AV_VERSION_INT(57, 25, 100)) {

@@ -287,6 +287,16 @@ void Kit_AdvanceDecoderOutput(Kit_Decoder *dec) {
     }

 }

 

+unsigned int Kit_GetDecoderOutputLength(Kit_Decoder *dec) {

+    assert(dec != NULL);

+    unsigned int len;

+    if(SDL_LockMutex(dec->output_lock) == 0) {

+        len = Kit_GetBufferLength(dec->buffer[KIT_DEC_BUF_OUT]);

+        SDL_UnlockMutex(dec->output_lock);

+    }

+    return len;

+}

+

 void Kit_ClearDecoderBuffers(Kit_Decoder *dec) {

     if(dec == NULL) return;

     Kit_ClearDecoderInput(dec);

diff --git a/src/internal/utils/kitbuffer.c b/src/internal/utils/kitbuffer.c
index 0133154..60ca831 100644
--- a/src/internal/utils/kitbuffer.c
+++ b/src/internal/utils/kitbuffer.c
@@ -18,6 +18,10 @@ Kit_Buffer* Kit_CreateBuffer(unsigned int size, Kit_BufferFreeCallback free_cb)
     return b;
 }
 
+unsigned int Kit_GetBufferLength(const Kit_Buffer *buffer) {
+    return buffer->write_p - buffer->read_p;
+}
+
 void Kit_DestroyBuffer(Kit_Buffer *buffer) {
     if(buffer == NULL) return;
     Kit_ClearBuffer(buffer);
diff --git a/src/internal/video/kitvideo.c b/src/internal/video/kitvideo.c
index cde5226..7fb3c30 100644
--- a/src/internal/video/kitvideo.c
+++ b/src/internal/video/kitvideo.c
@@ -249,38 +249,30 @@ int Kit_GetVideoDecoderData(Kit_Decoder *dec, SDL_Texture *texture) {
     assert(texture != NULL);

 

     Kit_VideoPacket *next_packet = NULL;

-    Kit_VideoPacket *packet = Kit_PeekDecoderOutput(dec);

+    Kit_VideoPacket *packet = NULL;

+    double sync_ts = 0;

+    unsigned int limit_rounds = 0;

+

+    // First, peek the next packet. Make sure we have something to read.

+    packet = next_packet = Kit_PeekDecoderOutput(dec);

     if(packet == NULL) {

         return 0;

     }

 

-    double sync_ts = _GetSystemTime() - dec->clock_sync;

-

-    // Check if we want the packet

+    // If packet should not yet be played, stop here and wait.

+    // If packet should have already been played, skip it and try to find a better packet.

+    // For video, we *try* to return a frame, even if we are out of sync. It is better than

+    // not showing anything.

+    sync_ts = _GetSystemTime() - dec->clock_sync;

     if(packet->pts > sync_ts + KIT_VIDEO_SYNC_THRESHOLD) {

-        // Video is ahead, don't show yet.

         return 0;

-    } else if(packet->pts < sync_ts - KIT_VIDEO_SYNC_THRESHOLD) {

-        // Video is lagging, skip until we find a good PTS to continue from.

+    }

+    limit_rounds = Kit_GetDecoderOutputLength(dec);

+    while(packet != NULL && packet->pts < sync_ts - KIT_VIDEO_SYNC_THRESHOLD && --limit_rounds) {

         Kit_AdvanceDecoderOutput(dec);

-        while(packet != NULL) {

-            next_packet = Kit_PeekDecoderOutput(dec);

-

-            // If next packet is valid, remove this one and jump to next.

-            if(next_packet != NULL) {

-                Kit_AdvanceDecoderOutput(dec);

-                free_out_video_packet_cb(packet);

-                packet = next_packet;

-            }

-

-            dec->clock_pos = packet->pts;

-            if(packet->pts > sync_ts - KIT_VIDEO_SYNC_THRESHOLD) {

-                break;

-            }

-        }

+        free_out_video_packet_cb(packet);

+        packet = Kit_PeekDecoderOutput(dec);

     }

-

-    // If we have no viable packet, just skip

     if(packet == NULL) {

         return 0;

     }