src/cobalt/media/formats/webm/webm_video_client.cc

// Copyright 2014 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 "cobalt/media/formats/webm/webm_video_client.h"

#include "cobalt/media/base/video_decoder_config.h"
#include "cobalt/media/formats/webm/webm_constants.h"

namespace cobalt {
namespace media {

namespace {
// Tries to parse |data| to extract the VP9 Profile ID, or returns Profile 0.
media::VideoCodecProfile GetVP9CodecProfile(const std::vector<uint8_t>& data) {
  // VP9 CodecPrivate (http://wiki.webmproject.org/vp9-codecprivate) might have
  // Profile information in the first field, if present.
  constexpr uint8_t kVP9ProfileFieldId = 0x01;
  constexpr uint8_t kVP9ProfileFieldLength = 1;
  if (data.size() < 3 || data[0] != kVP9ProfileFieldId ||
      data[1] != kVP9ProfileFieldLength || data[2] > 3) {
    return VP9PROFILE_PROFILE0;
  }
  return static_cast<VideoCodecProfile>(
      static_cast<size_t>(VP9PROFILE_PROFILE0) + data[2]);
}
}  // namespace

WebMVideoClient::WebMVideoClient(const scoped_refptr<MediaLog>& media_log)
    : media_log_(media_log), colour_parsed_(false) {
  Reset();
}

WebMVideoClient::~WebMVideoClient() {}

void WebMVideoClient::Reset() {
  pixel_width_ = -1;
  pixel_height_ = -1;
  crop_bottom_ = -1;
  crop_top_ = -1;
  crop_left_ = -1;
  crop_right_ = -1;
  display_width_ = -1;
  display_height_ = -1;
  display_unit_ = -1;
  alpha_mode_ = -1;
  inside_projection_list_ = false;
  colour_parsed_ = false;
}

bool WebMVideoClient::InitializeConfig(
    const std::string& codec_id, const std::vector<uint8_t>& codec_private,
    const EncryptionScheme& encryption_scheme, VideoDecoderConfig* config) {
  DCHECK(config);

  VideoCodec video_codec = kUnknownVideoCodec;
  VideoCodecProfile profile = VIDEO_CODEC_PROFILE_UNKNOWN;
  if (codec_id == "V_VP8") {
    video_codec = kCodecVP8;
    profile = VP8PROFILE_ANY;
  } else if (codec_id == "V_VP9") {
    video_codec = kCodecVP9;
    profile = GetVP9CodecProfile(codec_private);
  } else {
    MEDIA_LOG(ERROR, media_log_) << "Unsupported video codec_id " << codec_id;
    return false;
  }

  VideoPixelFormat format =
      (alpha_mode_ == 1) ? PIXEL_FORMAT_YV12A : PIXEL_FORMAT_YV12;

  if (pixel_width_ <= 0 || pixel_height_ <= 0) return false;

  // Set crop and display unit defaults if these elements are not present.
  if (crop_bottom_ == -1) crop_bottom_ = 0;

  if (crop_top_ == -1) crop_top_ = 0;

  if (crop_left_ == -1) crop_left_ = 0;

  if (crop_right_ == -1) crop_right_ = 0;

  if (display_unit_ == -1) display_unit_ = 0;

  math::Size coded_size(pixel_width_, pixel_height_);
  math::RectF visible_rect_float(crop_top_, crop_left_,
                                 pixel_width_ - (crop_left_ + crop_right_),
                                 pixel_height_ - (crop_top_ + crop_bottom_));
  math::Rect visible_rect = math::Rect::RoundFromRectF(visible_rect_float);
  if (display_unit_ == 0) {
    if (display_width_ <= 0) display_width_ = visible_rect.width();
    if (display_height_ <= 0) display_height_ = visible_rect.height();
  } else if (display_unit_ == 3) {
    if (display_width_ <= 0 || display_height_ <= 0) return false;
  } else {
    MEDIA_LOG(ERROR, media_log_)
        << "Unsupported display unit type " << display_unit_;
    return false;
  }
  math::Size natural_size = math::Size(display_width_, display_height_);

  config->Initialize(video_codec, profile, format, COLOR_SPACE_HD_REC709,
                     coded_size, visible_rect, natural_size, codec_private,
                     encryption_scheme);
  if (colour_parsed_) {
    WebMColorMetadata color_metadata = colour_parser_.GetWebMColorMetadata();
    config->set_webm_color_metadata(color_metadata);
  }
  return config->IsValidConfig();
}

WebMParserClient* WebMVideoClient::OnListStart(int id) {
  if (id == kWebMIdColour) {
    colour_parsed_ = false;
    return &colour_parser_;
  }

  if (id == kWebMIdProjection && !inside_projection_list_) {
    inside_projection_list_ = true;
    return this;
  }

  return this;
}

bool WebMVideoClient::OnListEnd(int id) {
  if (id == kWebMIdColour) colour_parsed_ = true;

  if (id == kWebMIdProjection && inside_projection_list_) {
    inside_projection_list_ = false;
    return true;
  }

  return true;
}

bool WebMVideoClient::OnUInt(int id, int64_t val) {
  if (inside_projection_list_) {
    // Accept and ignore all integer fields under kWebMIdProjection list. This
    // currently includes the kWebMIdProjectionType field.
    return true;
  }

  int64_t* dst = NULL;

  switch (id) {
    case kWebMIdPixelWidth:
      dst = &pixel_width_;
      break;
    case kWebMIdPixelHeight:
      dst = &pixel_height_;
      break;
    case kWebMIdPixelCropTop:
      dst = &crop_top_;
      break;
    case kWebMIdPixelCropBottom:
      dst = &crop_bottom_;
      break;
    case kWebMIdPixelCropLeft:
      dst = &crop_left_;
      break;
    case kWebMIdPixelCropRight:
      dst = &crop_right_;
      break;
    case kWebMIdDisplayWidth:
      dst = &display_width_;
      break;
    case kWebMIdDisplayHeight:
      dst = &display_height_;
      break;
    case kWebMIdDisplayUnit:
      dst = &display_unit_;
      break;
    case kWebMIdAlphaMode:
      dst = &alpha_mode_;
      break;
    default:
      return true;
  }

  if (*dst != -1) {
    MEDIA_LOG(ERROR, media_log_)
        << "Multiple values for id " << std::hex << id << " specified (" << *dst
        << " and " << val << ")";
    return false;
  }

  *dst = val;
  return true;
}

bool WebMVideoClient::OnBinary(int id, const uint8_t* data, int size) {
  if (inside_projection_list_) {
    // Accept and ignore all binary fields under kWebMIdProjection list. This
    // currently includes the kWebMIdProjectionPrivate field.
    return true;
  }

  // Accept binary fields we don't care about for now.
  return true;
}

bool WebMVideoClient::OnFloat(int id, double val) {
  if (inside_projection_list_) {
    // Accept and ignore float fields under kWebMIdProjection list. This
    // currently includes the kWebMIdProjectionPosePitch,
    // kWebMIdProjectionPoseYaw, kWebMIdProjectionPoseRoll fields.
    return true;
  }

  // Accept float fields we don't care about for now.
  return true;
}

}  // namespace media
}  // namespace cobalt