diff options
Diffstat (limited to 'media')
| -rw-r--r-- | media/filters/ffmpeg_video_decoder.cc | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/media/filters/ffmpeg_video_decoder.cc b/media/filters/ffmpeg_video_decoder.cc index d65a692..89d44df 100644 --- a/media/filters/ffmpeg_video_decoder.cc +++ b/media/filters/ffmpeg_video_decoder.cc @@ -9,6 +9,20 @@ namespace media { +// Always try to use two threads for video decoding. There is little reason +// not to since current day CPUs tend to be multi-core and we measured +// performance benefits on older machines such as P4s with hyperthreading. +// +// Handling decoding on separate threads also frees up the pipeline thread to +// continue processing. Although it'd be nice to have the option of a single +// decoding thread, FFmpeg treats having one thread the same as having zero +// threads (i.e., avcodec_decode_video() will execute on the calling thread). +// Yet another reason for having two threads :) +// +// TODO(scherkus): some video codecs might not like avcodec_thread_init() being +// called on them... should attempt to find out which ones those are! +static const int kDecodeThreads = 2; + FFmpegVideoDecoder::FFmpegVideoDecoder() : DecoderBase<VideoDecoder, VideoFrame>(NULL), width_(0), @@ -44,7 +58,9 @@ bool FFmpegVideoDecoder::OnInitialize(DemuxerStream* demuxer_stream) { codec_context_ = ffmpeg_demuxer_stream->av_stream()->codec; codec_context_->flags2 |= CODEC_FLAG2_FAST; // Enable faster H264 decode. AVCodec* codec = avcodec_find_decoder(codec_context_->codec_id); - if (!codec || avcodec_open(codec_context_, codec) < 0) { + if (!codec || + avcodec_thread_init(codec_context_, kDecodeThreads) < 0 || + avcodec_open(codec_context_, codec) < 0) { host_->Error(media::PIPELINE_ERROR_DECODE); return false; } |