root/media/ffmpeg/ffmpeg_common.cc

DEFINITIONS

1. ConvertFromTimeBase
2. ConvertToTimeBase
3. CodecIDToAudioCodec
4. AudioCodecToCodecID
5. CodecIDToVideoCodec
6. VideoCodecToCodecID
7. ProfileIDToVideoCodecProfile
8. VideoCodecProfileToProfileID
9. AVSampleFormatToSampleFormat
10. SampleFormatToAVSampleFormat
11. AVCodecContextToAudioDecoderConfig
12. AVStreamToAudioDecoderConfig
13. AudioDecoderConfigToAVCodecContext
14. AVStreamToVideoDecoderConfig
15. VideoDecoderConfigToAVCodecContext
16. ChannelLayoutToChromeChannelLayout
17. PixelFormatToVideoFormat
18. VideoFormatToPixelFormat

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/ffmpeg/ffmpeg_common.h"

#include "base/basictypes.h"
#include "base/logging.h"
#include "base/metrics/histogram.h"
#include "base/strings/string_number_conversions.h"
#include "media/base/decoder_buffer.h"
#include "media/base/video_frame.h"
#include "media/base/video_util.h"

namespace media {

// Why FF_INPUT_BUFFER_PADDING_SIZE? FFmpeg assumes all input buffers are
// padded. Check here to ensure FFmpeg only receives data padded to its
// specifications.
COMPILE_ASSERT(DecoderBuffer::kPaddingSize >= FF_INPUT_BUFFER_PADDING_SIZE,
               decoder_buffer_padding_size_does_not_fit_ffmpeg_requirement);

// Alignment requirement by FFmpeg for input and output buffers. This need to
// be updated to match FFmpeg when it changes.
#if defined(ARCH_CPU_ARM_FAMILY)
static const int kFFmpegBufferAddressAlignment = 16;
#else
static const int kFFmpegBufferAddressAlignment = 32;
#endif

// Check here to ensure FFmpeg only receives data aligned to its specifications.
COMPILE_ASSERT(
    DecoderBuffer::kAlignmentSize >= kFFmpegBufferAddressAlignment &&
    DecoderBuffer::kAlignmentSize % kFFmpegBufferAddressAlignment == 0,
    decoder_buffer_alignment_size_does_not_fit_ffmpeg_requirement);

// Allows faster SIMD YUV convert. Also, FFmpeg overreads/-writes occasionally.
// See video_get_buffer() in libavcodec/utils.c.
static const int kFFmpegOutputBufferPaddingSize = 16;

COMPILE_ASSERT(VideoFrame::kFrameSizePadding >= kFFmpegOutputBufferPaddingSize,
               video_frame_padding_size_does_not_fit_ffmpeg_requirement);

COMPILE_ASSERT(
    VideoFrame::kFrameAddressAlignment >= kFFmpegBufferAddressAlignment &&
    VideoFrame::kFrameAddressAlignment % kFFmpegBufferAddressAlignment == 0,
    video_frame_address_alignment_does_not_fit_ffmpeg_requirement);

static const AVRational kMicrosBase = { 1, base::Time::kMicrosecondsPerSecond };

base::TimeDelta ConvertFromTimeBase(const AVRational& time_base,
                                    int64 timestamp) {
  int64 microseconds = av_rescale_q(timestamp, time_base, kMicrosBase);
  return base::TimeDelta::FromMicroseconds(microseconds);
}

int64 ConvertToTimeBase(const AVRational& time_base,
                        const base::TimeDelta& timestamp) {
  return av_rescale_q(timestamp.InMicroseconds(), kMicrosBase, time_base);
}

// Converts an FFmpeg audio codec ID into its corresponding supported codec id.
static AudioCodec CodecIDToAudioCodec(AVCodecID codec_id) {
  switch (codec_id) {
    case AV_CODEC_ID_AAC:
      return kCodecAAC;
    case AV_CODEC_ID_MP3:
      return kCodecMP3;
    case AV_CODEC_ID_VORBIS:
      return kCodecVorbis;
    case AV_CODEC_ID_PCM_U8:
    case AV_CODEC_ID_PCM_S16LE:
    case AV_CODEC_ID_PCM_S24LE:
    case AV_CODEC_ID_PCM_F32LE:
      return kCodecPCM;
    case AV_CODEC_ID_PCM_S16BE:
      return kCodecPCM_S16BE;
    case AV_CODEC_ID_PCM_S24BE:
      return kCodecPCM_S24BE;
    case AV_CODEC_ID_FLAC:
      return kCodecFLAC;
    case AV_CODEC_ID_AMR_NB:
      return kCodecAMR_NB;
    case AV_CODEC_ID_AMR_WB:
      return kCodecAMR_WB;
    case AV_CODEC_ID_GSM_MS:
      return kCodecGSM_MS;
    case AV_CODEC_ID_PCM_ALAW:
      return kCodecPCM_ALAW;
    case AV_CODEC_ID_PCM_MULAW:
      return kCodecPCM_MULAW;
    case AV_CODEC_ID_OPUS:
      return kCodecOpus;
    default:
      DVLOG(1) << "Unknown audio CodecID: " << codec_id;
  }
  return kUnknownAudioCodec;
}

static AVCodecID AudioCodecToCodecID(AudioCodec audio_codec,
                                     SampleFormat sample_format) {
  switch (audio_codec) {
    case kCodecAAC:
      return AV_CODEC_ID_AAC;
    case kCodecMP3:
      return AV_CODEC_ID_MP3;
    case kCodecPCM:
      switch (sample_format) {
        case kSampleFormatU8:
          return AV_CODEC_ID_PCM_U8;
        case kSampleFormatS16:
          return AV_CODEC_ID_PCM_S16LE;
        case kSampleFormatS32:
          return AV_CODEC_ID_PCM_S24LE;
        case kSampleFormatF32:
          return AV_CODEC_ID_PCM_F32LE;
        default:
          DVLOG(1) << "Unsupported sample format: " << sample_format;
      }
      break;
    case kCodecPCM_S16BE:
      return AV_CODEC_ID_PCM_S16BE;
    case kCodecPCM_S24BE:
      return AV_CODEC_ID_PCM_S24BE;
    case kCodecVorbis:
      return AV_CODEC_ID_VORBIS;
    case kCodecFLAC:
      return AV_CODEC_ID_FLAC;
    case kCodecAMR_NB:
      return AV_CODEC_ID_AMR_NB;
    case kCodecAMR_WB:
      return AV_CODEC_ID_AMR_WB;
    case kCodecGSM_MS:
      return AV_CODEC_ID_GSM_MS;
    case kCodecPCM_ALAW:
      return AV_CODEC_ID_PCM_ALAW;
    case kCodecPCM_MULAW:
      return AV_CODEC_ID_PCM_MULAW;
    case kCodecOpus:
      return AV_CODEC_ID_OPUS;
    default:
      DVLOG(1) << "Unknown AudioCodec: " << audio_codec;
  }
  return AV_CODEC_ID_NONE;
}

// Converts an FFmpeg video codec ID into its corresponding supported codec id.
static VideoCodec CodecIDToVideoCodec(AVCodecID codec_id) {
  switch (codec_id) {
    case AV_CODEC_ID_H264:
      return kCodecH264;
    case AV_CODEC_ID_THEORA:
      return kCodecTheora;
    case AV_CODEC_ID_MPEG4:
      return kCodecMPEG4;
    case AV_CODEC_ID_VP8:
      return kCodecVP8;
    case AV_CODEC_ID_VP9:
      return kCodecVP9;
    default:
      DVLOG(1) << "Unknown video CodecID: " << codec_id;
  }
  return kUnknownVideoCodec;
}

static AVCodecID VideoCodecToCodecID(VideoCodec video_codec) {
  switch (video_codec) {
    case kCodecH264:
      return AV_CODEC_ID_H264;
    case kCodecTheora:
      return AV_CODEC_ID_THEORA;
    case kCodecMPEG4:
      return AV_CODEC_ID_MPEG4;
    case kCodecVP8:
      return AV_CODEC_ID_VP8;
    case kCodecVP9:
      return AV_CODEC_ID_VP9;
    default:
      DVLOG(1) << "Unknown VideoCodec: " << video_codec;
  }
  return AV_CODEC_ID_NONE;
}

static VideoCodecProfile ProfileIDToVideoCodecProfile(int profile) {
  // Clear out the CONSTRAINED & INTRA flags which are strict subsets of the
  // corresponding profiles with which they're used.
  profile &= ~FF_PROFILE_H264_CONSTRAINED;
  profile &= ~FF_PROFILE_H264_INTRA;
  switch (profile) {
    case FF_PROFILE_H264_BASELINE:
      return H264PROFILE_BASELINE;
    case FF_PROFILE_H264_MAIN:
      return H264PROFILE_MAIN;
    case FF_PROFILE_H264_EXTENDED:
      return H264PROFILE_EXTENDED;
    case FF_PROFILE_H264_HIGH:
      return H264PROFILE_HIGH;
    case FF_PROFILE_H264_HIGH_10:
      return H264PROFILE_HIGH10PROFILE;
    case FF_PROFILE_H264_HIGH_422:
      return H264PROFILE_HIGH422PROFILE;
    case FF_PROFILE_H264_HIGH_444_PREDICTIVE:
      return H264PROFILE_HIGH444PREDICTIVEPROFILE;
    default:
      DVLOG(1) << "Unknown profile id: " << profile;
  }
  return VIDEO_CODEC_PROFILE_UNKNOWN;
}

static int VideoCodecProfileToProfileID(VideoCodecProfile profile) {
  switch (profile) {
    case H264PROFILE_BASELINE:
      return FF_PROFILE_H264_BASELINE;
    case H264PROFILE_MAIN:
      return FF_PROFILE_H264_MAIN;
    case H264PROFILE_EXTENDED:
      return FF_PROFILE_H264_EXTENDED;
    case H264PROFILE_HIGH:
      return FF_PROFILE_H264_HIGH;
    case H264PROFILE_HIGH10PROFILE:
      return FF_PROFILE_H264_HIGH_10;
    case H264PROFILE_HIGH422PROFILE:
      return FF_PROFILE_H264_HIGH_422;
    case H264PROFILE_HIGH444PREDICTIVEPROFILE:
      return FF_PROFILE_H264_HIGH_444_PREDICTIVE;
    default:
      DVLOG(1) << "Unknown VideoCodecProfile: " << profile;
  }
  return FF_PROFILE_UNKNOWN;
}

SampleFormat AVSampleFormatToSampleFormat(AVSampleFormat sample_format) {
  switch (sample_format) {
    case AV_SAMPLE_FMT_U8:
      return kSampleFormatU8;
    case AV_SAMPLE_FMT_S16:
      return kSampleFormatS16;
    case AV_SAMPLE_FMT_S32:
      return kSampleFormatS32;
    case AV_SAMPLE_FMT_FLT:
      return kSampleFormatF32;
    case AV_SAMPLE_FMT_S16P:
      return kSampleFormatPlanarS16;
    case AV_SAMPLE_FMT_FLTP:
      return kSampleFormatPlanarF32;
    default:
      DVLOG(1) << "Unknown AVSampleFormat: " << sample_format;
  }
  return kUnknownSampleFormat;
}

static AVSampleFormat SampleFormatToAVSampleFormat(SampleFormat sample_format) {
  switch (sample_format) {
    case kSampleFormatU8:
      return AV_SAMPLE_FMT_U8;
    case kSampleFormatS16:
      return AV_SAMPLE_FMT_S16;
    case kSampleFormatS32:
      return AV_SAMPLE_FMT_S32;
    case kSampleFormatF32:
      return AV_SAMPLE_FMT_FLT;
    case kSampleFormatPlanarS16:
      return AV_SAMPLE_FMT_S16P;
    case kSampleFormatPlanarF32:
      return AV_SAMPLE_FMT_FLTP;
    default:
      DVLOG(1) << "Unknown SampleFormat: " << sample_format;
  }
  return AV_SAMPLE_FMT_NONE;
}

static void AVCodecContextToAudioDecoderConfig(
    const AVCodecContext* codec_context,
    bool is_encrypted,
    AudioDecoderConfig* config,
    bool record_stats) {
  DCHECK_EQ(codec_context->codec_type, AVMEDIA_TYPE_AUDIO);

  AudioCodec codec = CodecIDToAudioCodec(codec_context->codec_id);

  SampleFormat sample_format =
      AVSampleFormatToSampleFormat(codec_context->sample_fmt);

  ChannelLayout channel_layout = ChannelLayoutToChromeChannelLayout(
      codec_context->channel_layout, codec_context->channels);

  if (codec == kCodecOpus) {
    // |codec_context->sample_fmt| is not set by FFmpeg because Opus decoding is
    // not enabled in FFmpeg.  It doesn't matter what value is set here, so long
    // as it's valid, the true sample format is selected inside the decoder.
    sample_format = kSampleFormatF32;
  }

  base::TimeDelta seek_preroll;
  if (codec_context->seek_preroll > 0) {
    seek_preroll = base::TimeDelta::FromMicroseconds(
        codec_context->seek_preroll * 1000000.0 / codec_context->sample_rate);
  }

  base::TimeDelta codec_delay;
  if (codec_context->delay > 0) {
    codec_delay = base::TimeDelta::FromMicroseconds(
        codec_context->delay * 1000000.0 / codec_context->sample_rate);
  }

  config->Initialize(codec,
                     sample_format,
                     channel_layout,
                     codec_context->sample_rate,
                     codec_context->extradata,
                     codec_context->extradata_size,
                     is_encrypted,
                     record_stats,
                     seek_preroll,
                     codec_delay);
  if (codec != kCodecOpus) {
    DCHECK_EQ(av_get_bytes_per_sample(codec_context->sample_fmt) * 8,
              config->bits_per_channel());
  }
}

void AVStreamToAudioDecoderConfig(
    const AVStream* stream,
    AudioDecoderConfig* config,
    bool record_stats) {
  bool is_encrypted = false;
  AVDictionaryEntry* key = av_dict_get(stream->metadata, "enc_key_id", NULL, 0);
  if (key)
    is_encrypted = true;
  return AVCodecContextToAudioDecoderConfig(
      stream->codec, is_encrypted, config, record_stats);
}

void AudioDecoderConfigToAVCodecContext(const AudioDecoderConfig& config,
                                        AVCodecContext* codec_context) {
  codec_context->codec_type = AVMEDIA_TYPE_AUDIO;
  codec_context->codec_id = AudioCodecToCodecID(config.codec(),
                                                config.sample_format());
  codec_context->sample_fmt = SampleFormatToAVSampleFormat(
      config.sample_format());

  // TODO(scherkus): should we set |channel_layout|? I'm not sure if FFmpeg uses
  // said information to decode.
  codec_context->channels =
      ChannelLayoutToChannelCount(config.channel_layout());
  codec_context->sample_rate = config.samples_per_second();

  if (config.extra_data()) {
    codec_context->extradata_size = config.extra_data_size();
    codec_context->extradata = reinterpret_cast<uint8_t*>(
        av_malloc(config.extra_data_size() + FF_INPUT_BUFFER_PADDING_SIZE));
    memcpy(codec_context->extradata, config.extra_data(),
           config.extra_data_size());
    memset(codec_context->extradata + config.extra_data_size(), '\0',
           FF_INPUT_BUFFER_PADDING_SIZE);
  } else {
    codec_context->extradata = NULL;
    codec_context->extradata_size = 0;
  }
}

void AVStreamToVideoDecoderConfig(
    const AVStream* stream,
    VideoDecoderConfig* config,
    bool record_stats) {
  gfx::Size coded_size(stream->codec->coded_width, stream->codec->coded_height);

  // TODO(vrk): This assumes decoded frame data starts at (0, 0), which is true
  // for now, but may not always be true forever. Fix this in the future.
  gfx::Rect visible_rect(stream->codec->width, stream->codec->height);

  AVRational aspect_ratio = { 1, 1 };
  if (stream->sample_aspect_ratio.num)
    aspect_ratio = stream->sample_aspect_ratio;
  else if (stream->codec->sample_aspect_ratio.num)
    aspect_ratio = stream->codec->sample_aspect_ratio;

  VideoCodec codec = CodecIDToVideoCodec(stream->codec->codec_id);

  VideoCodecProfile profile = VIDEO_CODEC_PROFILE_UNKNOWN;
  if (codec == kCodecVP8)
    profile = VP8PROFILE_MAIN;
  else if (codec == kCodecVP9)
    profile = VP9PROFILE_MAIN;
  else
    profile = ProfileIDToVideoCodecProfile(stream->codec->profile);

  gfx::Size natural_size = GetNaturalSize(
      visible_rect.size(), aspect_ratio.num, aspect_ratio.den);

  if (record_stats) {
    // Note the PRESUBMIT_IGNORE_UMA_MAX below, this silences the PRESUBMIT.py
    // check for uma enum max usage, since we're abusing
    // UMA_HISTOGRAM_ENUMERATION to report a discrete value.
    UMA_HISTOGRAM_ENUMERATION("Media.VideoColorRange",
                              stream->codec->color_range,
                              AVCOL_RANGE_NB);  // PRESUBMIT_IGNORE_UMA_MAX
  }

  VideoFrame::Format format = PixelFormatToVideoFormat(stream->codec->pix_fmt);
  if (codec == kCodecVP9) {
    // TODO(tomfinegan): libavcodec doesn't know about VP9.
    format = VideoFrame::YV12;
    coded_size = natural_size;
  }

  // Pad out |coded_size| for subsampled YUV formats.
  coded_size.set_width((coded_size.width() + 1) / 2 * 2);
  if (format != VideoFrame::YV16)
    coded_size.set_height((coded_size.height() + 1) / 2 * 2);

  bool is_encrypted = false;
  AVDictionaryEntry* key = av_dict_get(stream->metadata, "enc_key_id", NULL, 0);
  if (key)
    is_encrypted = true;

  AVDictionaryEntry* webm_alpha =
      av_dict_get(stream->metadata, "alpha_mode", NULL, 0);
  if (webm_alpha && !strcmp(webm_alpha->value, "1")) {
    format = VideoFrame::YV12A;
  }

  config->Initialize(codec,
                     profile,
                     format,
                     coded_size, visible_rect, natural_size,
                     stream->codec->extradata, stream->codec->extradata_size,
                     is_encrypted,
                     record_stats);
}

void VideoDecoderConfigToAVCodecContext(
    const VideoDecoderConfig& config,
    AVCodecContext* codec_context) {
  codec_context->codec_type = AVMEDIA_TYPE_VIDEO;
  codec_context->codec_id = VideoCodecToCodecID(config.codec());
  codec_context->profile = VideoCodecProfileToProfileID(config.profile());
  codec_context->coded_width = config.coded_size().width();
  codec_context->coded_height = config.coded_size().height();
  codec_context->pix_fmt = VideoFormatToPixelFormat(config.format());

  if (config.extra_data()) {
    codec_context->extradata_size = config.extra_data_size();
    codec_context->extradata = reinterpret_cast<uint8_t*>(
        av_malloc(config.extra_data_size() + FF_INPUT_BUFFER_PADDING_SIZE));
    memcpy(codec_context->extradata, config.extra_data(),
           config.extra_data_size());
    memset(codec_context->extradata + config.extra_data_size(), '\0',
           FF_INPUT_BUFFER_PADDING_SIZE);
  } else {
    codec_context->extradata = NULL;
    codec_context->extradata_size = 0;
  }
}

ChannelLayout ChannelLayoutToChromeChannelLayout(int64_t layout, int channels) {
  switch (layout) {
    case AV_CH_LAYOUT_MONO:
      return CHANNEL_LAYOUT_MONO;
    case AV_CH_LAYOUT_STEREO:
      return CHANNEL_LAYOUT_STEREO;
    case AV_CH_LAYOUT_2_1:
      return CHANNEL_LAYOUT_2_1;
    case AV_CH_LAYOUT_SURROUND:
      return CHANNEL_LAYOUT_SURROUND;
    case AV_CH_LAYOUT_4POINT0:
      return CHANNEL_LAYOUT_4_0;
    case AV_CH_LAYOUT_2_2:
      return CHANNEL_LAYOUT_2_2;
    case AV_CH_LAYOUT_QUAD:
      return CHANNEL_LAYOUT_QUAD;
    case AV_CH_LAYOUT_5POINT0:
      return CHANNEL_LAYOUT_5_0;
    case AV_CH_LAYOUT_5POINT1:
      return CHANNEL_LAYOUT_5_1;
    case AV_CH_LAYOUT_5POINT0_BACK:
      return CHANNEL_LAYOUT_5_0_BACK;
    case AV_CH_LAYOUT_5POINT1_BACK:
      return CHANNEL_LAYOUT_5_1_BACK;
    case AV_CH_LAYOUT_7POINT0:
      return CHANNEL_LAYOUT_7_0;
    case AV_CH_LAYOUT_7POINT1:
      return CHANNEL_LAYOUT_7_1;
    case AV_CH_LAYOUT_7POINT1_WIDE:
      return CHANNEL_LAYOUT_7_1_WIDE;
    case AV_CH_LAYOUT_STEREO_DOWNMIX:
      return CHANNEL_LAYOUT_STEREO_DOWNMIX;
    case AV_CH_LAYOUT_2POINT1:
      return CHANNEL_LAYOUT_2POINT1;
    case AV_CH_LAYOUT_3POINT1:
      return CHANNEL_LAYOUT_3_1;
    case AV_CH_LAYOUT_4POINT1:
      return CHANNEL_LAYOUT_4_1;
    case AV_CH_LAYOUT_6POINT0:
      return CHANNEL_LAYOUT_6_0;
    case AV_CH_LAYOUT_6POINT0_FRONT:
      return CHANNEL_LAYOUT_6_0_FRONT;
    case AV_CH_LAYOUT_HEXAGONAL:
      return CHANNEL_LAYOUT_HEXAGONAL;
    case AV_CH_LAYOUT_6POINT1:
      return CHANNEL_LAYOUT_6_1;
    case AV_CH_LAYOUT_6POINT1_BACK:
      return CHANNEL_LAYOUT_6_1_BACK;
    case AV_CH_LAYOUT_6POINT1_FRONT:
      return CHANNEL_LAYOUT_6_1_FRONT;
    case AV_CH_LAYOUT_7POINT0_FRONT:
      return CHANNEL_LAYOUT_7_0_FRONT;
#ifdef AV_CH_LAYOUT_7POINT1_WIDE_BACK
    case AV_CH_LAYOUT_7POINT1_WIDE_BACK:
      return CHANNEL_LAYOUT_7_1_WIDE_BACK;
#endif
    case AV_CH_LAYOUT_OCTAGONAL:
      return CHANNEL_LAYOUT_OCTAGONAL;
    default:
      // FFmpeg channel_layout is 0 for .wav and .mp3.  Attempt to guess layout
      // based on the channel count.
      return GuessChannelLayout(channels);
  }
}

VideoFrame::Format PixelFormatToVideoFormat(PixelFormat pixel_format) {
  switch (pixel_format) {
    case PIX_FMT_YUV422P:
      return VideoFrame::YV16;
    case PIX_FMT_YUV420P:
      return VideoFrame::YV12;
    case PIX_FMT_YUVJ420P:
      return VideoFrame::YV12J;
    case PIX_FMT_YUVA420P:
      return VideoFrame::YV12A;
    default:
      DVLOG(1) << "Unsupported PixelFormat: " << pixel_format;
  }
  return VideoFrame::UNKNOWN;
}

PixelFormat VideoFormatToPixelFormat(VideoFrame::Format video_format) {
  switch (video_format) {
    case VideoFrame::YV16:
      return PIX_FMT_YUV422P;
    case VideoFrame::YV12:
      return PIX_FMT_YUV420P;
    case VideoFrame::YV12J:
      return PIX_FMT_YUVJ420P;
    case VideoFrame::YV12A:
      return PIX_FMT_YUVA420P;
    default:
      DVLOG(1) << "Unsupported VideoFrame::Format: " << video_format;
  }
  return PIX_FMT_NONE;
}

}  // namespace media