Commit 5e4e1fa4 authored by flx42's avatar flx42
Browse files

mediacodec: use a circular buffer of timestamps as a workaround for DTS only samples

parent 26bcd87e
......@@ -54,6 +54,80 @@ extern void jni_SetAndroidSurfaceSizeEnv(JNIEnv *p_env, int width, int height, i
extern void jni_EventHardwareAccelerationError();
extern bool jni_IsVideoPlayerActivityCreated();
/* Implementation of a circular buffer of timestamps with overwriting
* of older values. MediaCodec has only one type of timestamp, if a
* block has no PTS, we send the DTS instead. Some hardware decoders
* cannot cope with this situation and output the frames in the wrong
* order. As a workaround in this case, we use a FIFO of timestamps in
* order to remember which input packets had no PTS. Since an
* hardware decoder can silently drop frames, this might cause a
* growing desynchronization with the actual timestamp. Thus the
* circular buffer has a limited size and will overwrite older values.
*/
typedef struct
{
uint32_t begin;
uint32_t size;
uint32_t capacity;
int64_t *buffer;
} timestamp_fifo_t;
static timestamp_fifo_t *timestamp_FifoNew(uint32_t capacity)
{
timestamp_fifo_t *fifo = calloc(1, sizeof(*fifo));
if (!fifo)
return NULL;
fifo->buffer = malloc(capacity * sizeof(*fifo->buffer));
if (!fifo->buffer) {
free(fifo);
return NULL;
}
fifo->capacity = capacity;
return fifo;
}
static void timestamp_FifoRelease(timestamp_fifo_t *fifo)
{
free(fifo->buffer);
free(fifo);
}
static bool timestamp_FifoIsEmpty(timestamp_fifo_t *fifo)
{
return fifo->size == 0;
}
static bool timestamp_FifoIsFull(timestamp_fifo_t *fifo)
{
return fifo->size == fifo->capacity;
}
static void timestamp_FifoEmpty(timestamp_fifo_t *fifo)
{
fifo->size = 0;
}
static void timestamp_FifoPut(timestamp_fifo_t *fifo, int64_t ts)
{
uint32_t end = (fifo->begin + fifo->size) % fifo->capacity;
fifo->buffer[end] = ts;
if (!timestamp_FifoIsFull(fifo))
fifo->size += 1;
else
fifo->begin = (fifo->begin + 1) % fifo->capacity;
}
static int64_t timestamp_FifoGet(timestamp_fifo_t *fifo)
{
if (timestamp_FifoIsEmpty(fifo))
return VLC_TS_INVALID;
int64_t result = fifo->buffer[fifo->begin];
fifo->begin = (fifo->begin + 1) % fifo->capacity;
fifo->size -= 1;
return result;
}
struct decoder_sys_t
{
jclass media_codec_list_class, media_codec_class, media_format_class;
......@@ -92,6 +166,8 @@ struct decoder_sys_t
bool direct_rendering;
int i_output_buffers; /**< number of MediaCodec output buffers */
picture_t** inflight_picture; /**< stores the inflight picture for each output buffer or NULL */
timestamp_fifo_t *timestamp_fifo;
};
enum Types
......@@ -451,6 +527,12 @@ static int OpenDecoder(vlc_object_t *p_this)
(*env)->DeleteLocalRef(env, format);
(*myVm)->DetachCurrentThread(myVm);
const int timestamp_fifo_size = 32;
p_sys->timestamp_fifo = timestamp_FifoNew(timestamp_fifo_size);
if (!p_sys->timestamp_fifo)
goto error;
return VLC_SUCCESS;
error:
......@@ -490,6 +572,8 @@ static void CloseDecoder(vlc_object_t *p_this)
free(p_sys->name);
ArchitectureSpecificCopyHooksDestroy(p_sys->pixel_format, &p_sys->architecture_specific_data);
free(p_sys->inflight_picture);
if (p_sys->timestamp_fifo)
timestamp_FifoRelease(p_sys->timestamp_fifo);
free(p_sys);
}
......@@ -591,7 +675,16 @@ static void GetOutput(decoder_t *p_dec, JNIEnv *env, picture_t **pp_pic, jlong t
// TODO: Use crop_top/crop_left as well? Or is that already taken into account?
// On OMX_TI_COLOR_FormatYUV420PackedSemiPlanar the offset already incldues
// the cropping, so the top/left cropping params should just be ignored.
p_pic->date = (*env)->GetLongField(env, p_sys->buffer_info, p_sys->pts_field);
/* If the oldest input block had no PTS, the timestamp
* of the frame returned by MediaCodec might be wrong
* so we overwrite it with the corresponding dts. */
int64_t forced_ts = timestamp_FifoGet(p_sys->timestamp_fifo);
if (forced_ts == VLC_TS_INVALID)
p_pic->date = (*env)->GetLongField(env, p_sys->buffer_info, p_sys->pts_field);
else
p_pic->date = forced_ts;
if (p_sys->direct_rendering) {
picture_sys_t *p_picsys = p_pic->p_sys;
p_picsys->pf_display_callback = DisplayCallback;
......@@ -741,6 +834,7 @@ static picture_t *DecodeVideo(decoder_t *p_dec, block_t **pp_block)
if (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED)) {
block_Release(p_block);
timestamp_FifoEmpty(p_sys->timestamp_fifo);
if (p_sys->decoded) {
/* Invalidate all pictures that are currently in flight
* since flushing make all previous indices returned by
......@@ -831,6 +925,7 @@ static picture_t *DecodeVideo(decoder_t *p_dec, block_t **pp_block)
int64_t ts = p_block->i_pts;
if (!ts && p_block->i_dts)
ts = p_block->i_dts;
timestamp_FifoPut(p_sys->timestamp_fifo, p_block->i_pts ? VLC_TS_INVALID : p_block->i_dts);
(*env)->CallVoidMethod(env, p_sys->codec, p_sys->queue_input_buffer, index, 0, size, ts, 0);
(*env)->DeleteLocalRef(env, buf);
p_sys->decoded = true;
......
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