[FFmpeg-devel] [PATCH v4] Improved the performance of 1 decode + N filter graphs and adaptive bitrate.
Shaofei Wang
shaofei.wang at intel.com
Tue Feb 12 00:41:04 EET 2019
It enabled multiple filter graph concurrency, which bring above about
4%~20% improvement in some 1:N scenarios by CPU or GPU acceleration
Below are some test cases and comparison as reference.
(Hardware platform: Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz)
(Software: Intel iHD driver - 16.9.00100, CentOS 7)
For 1:N transcode by GPU acceleration with vaapi:
./ffmpeg -vaapi_device /dev/dri/renderD128 -hwaccel vaapi \
-hwaccel_output_format vaapi \
-i ~/Videos/1920x1080p_30.00_x264_qp28.h264 \
-vf "scale_vaapi=1280:720" -c:v h264_vaapi -f null /dev/null \
-vf "scale_vaapi=720:480" -c:v h264_vaapi -f null /dev/null
test results:
2 encoders 5 encoders 10 encoders
Improved 6.1% 6.9% 5.5%
For 1:N transcode by GPU acceleration with QSV:
./ffmpeg -hwaccel qsv -c:v h264_qsv \
-i ~/Videos/1920x1080p_30.00_x264_qp28.h264 \
-vf "scale_qsv=1280:720:format=nv12" -c:v h264_qsv -f null /dev/null \
-vf "scale_qsv=720:480:format=nv12" -c:v h264_qsv -f null /dev/null
test results:
2 encoders 5 encoders 10 encoders
Improved 6% 4% 15%
For Intel GPU acceleration case, 1 decode to N scaling, by QSV:
./ffmpeg -hwaccel qsv -c:v h264_qsv \
-i ~/Videos/1920x1080p_30.00_x264_qp28.h264 \
-vf "scale_qsv=1280:720:format=nv12,hwdownload" -pix_fmt nv12 -f null /dev/null \
-vf "scale_qsv=720:480:format=nv12,hwdownload" -pix_fmt nv12 -f null /dev/null
test results:
2 scale 5 scale 10 scale
Improved 12% 21% 21%
For CPU only 1 decode to N scaling:
./ffmpeg -i ~/Videos/1920x1080p_30.00_x264_qp28.h264 \
-vf "scale=1280:720" -pix_fmt nv12 -f null /dev/null \
-vf "scale=720:480" -pix_fmt nv12 -f null /dev/null
test results:
2 scale 5 scale 10 scale
Improved 25% 107% 148%
Signed-off-by: Wang, Shaofei <shaofei.wang at intel.com>
Reviewed-by: Zhao, Jun <jun.zhao at intel.com>
---
fftools/ffmpeg.c | 112 +++++++++++++++++++++++++++++++++++++++++++++---
fftools/ffmpeg.h | 14 ++++++
fftools/ffmpeg_filter.c | 4 ++
3 files changed, 124 insertions(+), 6 deletions(-)
diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
index 544f1a1..67b1a2a 100644
--- a/fftools/ffmpeg.c
+++ b/fftools/ffmpeg.c
@@ -1419,13 +1419,18 @@ static void finish_output_stream(OutputStream *ost)
*
* @return 0 for success, <0 for severe errors
*/
-static int reap_filters(int flush)
+static int reap_filters(int flush, InputFilter * ifilter)
{
AVFrame *filtered_frame = NULL;
int i;
- /* Reap all buffers present in the buffer sinks */
+ /* Reap all buffers present in the buffer sinks or just reap specified
+ * input filter buffer */
for (i = 0; i < nb_output_streams; i++) {
+ if (ifilter) {
+ if (ifilter != output_streams[i]->filter->graph->inputs[0])
+ continue;
+ }
OutputStream *ost = output_streams[i];
OutputFile *of = output_files[ost->file_index];
AVFilterContext *filter;
@@ -2179,7 +2184,8 @@ static int ifilter_send_frame(InputFilter *ifilter, AVFrame *frame)
}
}
- ret = reap_filters(1);
+ ret = HAVE_THREADS ? reap_filters(1, ifilter) : reap_filters(1, NULL);
+
if (ret < 0 && ret != AVERROR_EOF) {
av_log(NULL, AV_LOG_ERROR, "Error while filtering: %s\n", av_err2str(ret));
return ret;
@@ -2208,6 +2214,14 @@ static int ifilter_send_eof(InputFilter *ifilter, int64_t pts)
ifilter->eof = 1;
+#if HAVE_THREADS
+ ifilter->waited_frm = NULL;
+ pthread_mutex_lock(&ifilter->process_mutex);
+ ifilter->t_end = 1;
+ pthread_cond_signal(&ifilter->process_cond);
+ pthread_mutex_unlock(&ifilter->process_mutex);
+ pthread_join(ifilter->f_thread, NULL);
+#endif
if (ifilter->filter) {
ret = av_buffersrc_close(ifilter->filter, pts, AV_BUFFERSRC_FLAG_PUSH);
if (ret < 0)
@@ -2252,12 +2266,95 @@ static int decode(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacke
return 0;
}
+#if HAVE_THREADS
+static void *filter_pipeline(void *arg)
+{
+ InputFilter *fl = arg;
+ AVFrame *frm;
+ int ret;
+ while(1) {
+ pthread_mutex_lock(&fl->process_mutex);
+ while (fl->waited_frm == NULL && !fl->t_end)
+ pthread_cond_wait(&fl->process_cond, &fl->process_mutex);
+ pthread_mutex_unlock(&fl->process_mutex);
+
+ if (fl->t_end) break;
+
+ frm = fl->waited_frm;
+ ret = ifilter_send_frame(fl, frm);
+ if (ret < 0) {
+ av_log(NULL, AV_LOG_ERROR,
+ "Failed to inject frame into filter network: %s\n", av_err2str(ret));
+ } else {
+ ret = reap_filters(0, fl);
+ }
+ fl->t_error = ret;
+
+ pthread_mutex_lock(&fl->finish_mutex);
+ fl->waited_frm = NULL;
+ pthread_cond_signal(&fl->finish_cond);
+ pthread_mutex_unlock(&fl->finish_mutex);
+
+ if (ret < 0)
+ break;
+ }
+ return fl;
+}
+#endif
+
static int send_frame_to_filters(InputStream *ist, AVFrame *decoded_frame)
{
int i, ret;
AVFrame *f;
av_assert1(ist->nb_filters > 0); /* ensure ret is initialized */
+#if HAVE_THREADS
+ for (i = 0; i < ist->nb_filters; i++) {
+ //it will use abr_pipeline mode by default
+ if (i < ist->nb_filters - 1) {
+ f = &ist->filters[i]->input_frm;
+ ret = av_frame_ref(f, decoded_frame);
+ if (ret < 0)
+ break;
+ } else
+ f = decoded_frame;
+
+ if (!ist->filters[i]->b_abr_thread_init) {
+ if ((ret = pthread_create(&ist->filters[i]->f_thread, NULL, filter_pipeline,
+ ist->filters[i]))) {
+ av_log(NULL, AV_LOG_ERROR,
+ "pthread_create failed: %s. Try to increase `ulimit -v` or \
+ decrease `ulimit -s`.\n", strerror(ret));
+ return AVERROR(ret);
+ }
+ pthread_mutex_init(&ist->filters[i]->process_mutex, NULL);
+ pthread_mutex_init(&ist->filters[i]->finish_mutex, NULL);
+ pthread_cond_init(&ist->filters[i]->process_cond, NULL);
+ pthread_cond_init(&ist->filters[i]->finish_cond, NULL);
+ ist->filters[i]->t_end = 0;
+ ist->filters[i]->t_error = 0;
+ ist->filters[i]->b_abr_thread_init = 1;
+ }
+
+ pthread_mutex_lock(&ist->filters[i]->process_mutex);
+ ist->filters[i]->waited_frm = f;
+ pthread_cond_signal(&ist->filters[i]->process_cond);
+ pthread_mutex_unlock(&ist->filters[i]->process_mutex);
+ }
+
+ for (i = 0; i < ist->nb_filters; i++) {
+ pthread_mutex_lock(&ist->filters[i]->finish_mutex);
+ while(ist->filters[i]->waited_frm != NULL)
+ pthread_cond_wait(&ist->filters[i]->finish_cond, &ist->filters[i]->finish_mutex);
+ pthread_mutex_unlock(&ist->filters[i]->finish_mutex);
+ }
+ for (i = 0; i < ist->nb_filters; i++) {
+ if (ist->filters[i]->t_error < 0) {
+ ret = ist->filters[i]->t_error;
+ break;
+ }
+ }
+#else
for (i = 0; i < ist->nb_filters; i++) {
if (i < ist->nb_filters - 1) {
f = ist->filter_frame;
@@ -2266,6 +2363,7 @@ static int send_frame_to_filters(InputStream *ist, AVFrame *decoded_frame)
break;
} else
f = decoded_frame;
+
ret = ifilter_send_frame(ist->filters[i], f);
if (ret == AVERROR_EOF)
ret = 0; /* ignore */
@@ -2275,6 +2373,8 @@ static int send_frame_to_filters(InputStream *ist, AVFrame *decoded_frame)
break;
}
}
+#endif
+
return ret;
}
@@ -4537,10 +4637,10 @@ static int transcode_from_filter(FilterGraph *graph, InputStream **best_ist)
*best_ist = NULL;
ret = avfilter_graph_request_oldest(graph->graph);
if (ret >= 0)
- return reap_filters(0);
+ return reap_filters(0, NULL);
if (ret == AVERROR_EOF) {
- ret = reap_filters(1);
+ ret = reap_filters(1, NULL);
for (i = 0; i < graph->nb_outputs; i++)
close_output_stream(graph->outputs[i]->ost);
return ret;
@@ -4642,7 +4742,7 @@ static int transcode_step(void)
if (ret < 0)
return ret == AVERROR_EOF ? 0 : ret;
- return reap_filters(0);
+ return HAVE_THREADS ? ret : reap_filters(0, NULL);
}
/*
diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h
index eb1eaf6..9a8e776 100644
--- a/fftools/ffmpeg.h
+++ b/fftools/ffmpeg.h
@@ -253,6 +253,20 @@ typedef struct InputFilter {
AVBufferRef *hw_frames_ctx;
+ // for abr pipeline
+ int b_abr_thread_init;
+#if HAVE_THREADS
+ AVFrame *waited_frm;
+ AVFrame input_frm;
+ pthread_t f_thread;
+ pthread_cond_t process_cond;
+ pthread_cond_t finish_cond;
+ pthread_mutex_t process_mutex;
+ pthread_mutex_t finish_mutex;
+ int t_end;
+ int t_error;
+#endif
+
int eof;
} InputFilter;
diff --git a/fftools/ffmpeg_filter.c b/fftools/ffmpeg_filter.c
index 6518d50..5d1e521 100644
--- a/fftools/ffmpeg_filter.c
+++ b/fftools/ffmpeg_filter.c
@@ -197,6 +197,7 @@ DEF_CHOOSE_FORMAT(channel_layouts, uint64_t, channel_layout, channel_layouts, 0,
int init_simple_filtergraph(InputStream *ist, OutputStream *ost)
{
FilterGraph *fg = av_mallocz(sizeof(*fg));
+ int i;
if (!fg)
exit_program(1);
@@ -225,6 +226,9 @@ int init_simple_filtergraph(InputStream *ist, OutputStream *ost)
GROW_ARRAY(ist->filters, ist->nb_filters);
ist->filters[ist->nb_filters - 1] = fg->inputs[0];
+ for (i = 0; i < ist->nb_filters; i++)
+ ist->filters[i]->b_abr_thread_init = 0;
+
GROW_ARRAY(filtergraphs, nb_filtergraphs);
filtergraphs[nb_filtergraphs - 1] = fg;
--
1.8.3.1
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