Chromecast: adds test frame-segmenter code to support CMA unit tests.

chromecast/media/cma/test/frame_segmenter_for_test.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 "chromecast/media/cma/test/frame_segmenter_for_test.h"
+
+#include "base/bind.h"
+#include "base/logging.h"
+#include "base/port.h"
+#include "chromecast/media/cma/base/decoder_buffer_adapter.h"
+#include "media/base/decoder_buffer.h"
+#include "media/base/demuxer.h"
+#include "media/base/media_log.h"
+#include "media/base/test_helpers.h"
+#include "media/ffmpeg/ffmpeg_common.h"
+#include "media/filters/ffmpeg_demuxer.h"
+#include "media/filters/file_data_source.h"
+#include "media/filters/h264_parser.h"
+#include "third_party/ffmpeg/ffmpeg_stubs.h"
+
+namespace chromecast {
+namespace media {
+
+namespace {
+
+struct AudioFrameHeader {
+  size_t offset;
+  size_t frame_size;
+  int sampling_frequency;
+};
+
+size_t mp3_bitrate[] = {
+  0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0 };
+size_t mp3_sample_rate[] = { 44100, 48000, 32000, 0 };
+
+AudioFrameHeader FindNextMp3Header(const uint8* data, size_t data_size) {
+  bool found = false;
+  AudioFrameHeader header;
+  header.frame_size = 0;
+  if (data_size < 4)
+    return header;
+
+  for (size_t k = 0; k < data_size - 4 && !found; k++) {
+    // Mp3 Header:
+    // syncword: 11111111111
+    // Mpeg1: 11
+    // Layer3: 01
+    if (!(data[k + 0] == 0xff && (data[k + 1] & 0xfe) == 0xfa))
+      continue;
+
+    int bitrate_index = (data[k + 2] >> 4);
+    if (bitrate_index == 0 || bitrate_index == 15) {
+      // Free size or bad bitrate => not supported.
+      continue;
+    }
+
+    int sample_rate_index = (data[k + 2] >> 2) & 0x3;
+    if (sample_rate_index == 3)
+      continue;
+
+    size_t frame_size =
+        ((1152 / 8) *  mp3_bitrate[bitrate_index] * 1000) /
+        mp3_sample_rate[sample_rate_index];
+    if (data[k + 2] & 0x2)
+      frame_size++;
+
+    // Make sure the frame is complete.
+    if (k + frame_size > data_size)
+      break;
+
+    if (k + frame_size < data_size - 3 &&
+        !(data[k + frame_size + 0] == 0xff &&
+          (data[k + frame_size + 1] & 0xfe) == 0xfa)) {
+      continue;
+    }
+
+    found = true;
+    header.offset = k;
+    header.frame_size = frame_size;
+    header.sampling_frequency = mp3_sample_rate[sample_rate_index];
+  }
+  return header;
+}
+
+}
+
+std::list<scoped_refptr<DecoderBufferBase> > Mp3SegmenterForTest(
+    const uint8* data, size_t data_size) {
+  size_t offset = 0;
+  std::list<scoped_refptr<DecoderBufferBase> > audio_frames;
+  base::TimeDelta timestamp;
+
+  while (true) {
+    AudioFrameHeader header = FindNextMp3Header(&data[offset],
+                                                data_size - offset);
+    if (header.frame_size == 0)
+      break;
+
+    header.offset += offset;
+    offset = header.offset + header.frame_size;
+
+    scoped_refptr< ::media::DecoderBuffer> buffer(
+         ::media::DecoderBuffer::CopyFrom(
+             &data[header.offset], header.frame_size));
+    buffer->set_timestamp(timestamp);
+    audio_frames.push_back(
+        scoped_refptr<DecoderBufferBase>(new DecoderBufferAdapter(buffer)));
+
+    // 1152 samples in an MP3 frame.
+    timestamp += base::TimeDelta::FromMicroseconds(
+        (GG_UINT64_C(1152) * 1000 * 1000) / header.sampling_frequency);
+  }
+  return audio_frames;
+}
+
+struct H264AccessUnit {
+  H264AccessUnit();
+
+  size_t offset;
+  size_t size;
+  int has_vcl;
+  int poc;
+};
+
+H264AccessUnit::H264AccessUnit()
+  : offset(0),
+    size(0),
+    has_vcl(false),
+    poc(0) {
+}
+
+std::list<scoped_refptr<DecoderBufferBase> > H264SegmenterForTest(
+    const uint8* data, size_t data_size) {
+  std::list<scoped_refptr<DecoderBufferBase> > video_frames;
+  std::list<H264AccessUnit> access_unit_list;
+  H264AccessUnit access_unit;
+
+  int prev_pic_order_cnt_lsb = 0;
+  int pic_order_cnt_msb = 0;
+
+  scoped_ptr< ::media::H264Parser> h264_parser(new ::media::H264Parser());
+  h264_parser->SetStream(data, data_size);
+
+  size_t offset = 0;
+  while (true) {
+    bool is_eos = false;
+    ::media::H264NALU nalu;
+    switch (h264_parser->AdvanceToNextNALU(&nalu)) {
+      case ::media::H264Parser::kOk:
+        break;
+      case ::media::H264Parser::kInvalidStream:
+      case ::media::H264Parser::kUnsupportedStream:
+        return video_frames;
+      case ::media::H264Parser::kEOStream:
+        is_eos = true;
+        break;
+    }
+    if (is_eos)
+      break;
+
+    // To get the NALU syncword offset, substract 3 or 4
+    // which corresponds to the possible syncword lengths.
+    size_t nalu_offset = nalu.data - data;
+    nalu_offset -= 3;
+    if (nalu_offset > 0 && data[nalu_offset-1] == 0)
+      nalu_offset--;
+
+    switch (nalu.nal_unit_type) {
+      case ::media::H264NALU::kAUD: {
+        break;
+      }
+      case ::media::H264NALU::kSPS: {
+        int sps_id;
+        if (h264_parser->ParseSPS(&sps_id) != ::media::H264Parser::kOk)
+          return video_frames;
+        if (access_unit.has_vcl) {
+          access_unit.size = nalu_offset - access_unit.offset;
+          access_unit_list.push_back(access_unit);
+          access_unit = H264AccessUnit();
+          access_unit.offset = nalu_offset;
+        }
+        break;
+      }
+      case ::media::H264NALU::kPPS: {
+        int pps_id;
+        if (h264_parser->ParsePPS(&pps_id) != ::media::H264Parser::kOk)
+          return video_frames;
+        if (access_unit.has_vcl) {
+          access_unit.size = nalu_offset - access_unit.offset;
+          access_unit_list.push_back(access_unit);
+          access_unit = H264AccessUnit();
+          access_unit.offset = nalu_offset;
+        }
+        break;
+      }
+      case ::media::H264NALU::kIDRSlice:
+      case ::media::H264NALU::kNonIDRSlice: {
+        ::media::H264SliceHeader shdr;
+        if (h264_parser->ParseSliceHeader(nalu, &shdr) !=
+            ::media::H264Parser::kOk) {
+          return video_frames;
+        }
+        const ::media::H264PPS* pps =
+            h264_parser->GetPPS(shdr.pic_parameter_set_id);
+        if (!pps)
+          return video_frames;
+        const ::media::H264SPS* sps =
+            h264_parser->GetSPS(pps->seq_parameter_set_id);
+
+        // Very simplified way to segment H264.
+        // This assumes only 1 VCL NALU per access unit.
+        if (access_unit.has_vcl) {
+          access_unit.size = nalu_offset - access_unit.offset;
+          access_unit_list.push_back(access_unit);
+          access_unit = H264AccessUnit();
+          access_unit.offset = nalu_offset;
+        }
+
+        access_unit.has_vcl = true;
+
+        // Support only explicit POC so far.
+        if (sps->pic_order_cnt_type != 0) {
+          LOG(WARNING) << "Unsupported pic_order_cnt_type";
+          return video_frames;
+        }
+        int diff_pic_order_cnt_lsb =
+            shdr.pic_order_cnt_lsb - prev_pic_order_cnt_lsb;
+        int max_pic_order_cnt_lsb =
+            1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4);
+        if (diff_pic_order_cnt_lsb < 0 &&
+            diff_pic_order_cnt_lsb <= -max_pic_order_cnt_lsb / 2) {
+          pic_order_cnt_msb += max_pic_order_cnt_lsb;
+        } else if (diff_pic_order_cnt_lsb > 0 &&
+                   diff_pic_order_cnt_lsb > max_pic_order_cnt_lsb / 2) {
+          pic_order_cnt_msb -= max_pic_order_cnt_lsb;
+        }
+        access_unit.poc = pic_order_cnt_msb + shdr.pic_order_cnt_lsb;
+        prev_pic_order_cnt_lsb = shdr.pic_order_cnt_lsb;
+        break;
+      }
+      default: {
+      }
+    }
+  }
+
+  // Emit the last access unit.
+  if (access_unit.has_vcl) {
+    access_unit.size = data_size - access_unit.offset;
+    access_unit_list.push_back(access_unit);
+  }
+
+  // Create the list of buffers.
+  // Totally arbitrary decision: assume a delta POC of 1 is 20ms (50Hz field
+  // rate).
+  base::TimeDelta poc_duration = base::TimeDelta::FromMilliseconds(20);
+  for (std::list<H264AccessUnit>::iterator it = access_unit_list.begin();
+       it != access_unit_list.end(); ++it) {
+    scoped_refptr< ::media::DecoderBuffer> buffer(
+        ::media::DecoderBuffer::CopyFrom(&data[it->offset], it->size));
+    buffer->set_timestamp(it->poc * poc_duration);
+    video_frames.push_back(
+        scoped_refptr<DecoderBufferBase>(new DecoderBufferAdapter(buffer)));
+  }
+
+  return video_frames;
+}
+
+void FFDemuxNeedKeyCB(const std::string& type,
+                      const std::vector<uint8>& init_data) {
+  LOG(FATAL) << "Unexpected test failure: file is encrypted.";
+}
+
+void DemuxReadCB(BufferList* buffer_list,
+                 ::media::DemuxerStream::Status status,
+                 const scoped_refptr< ::media::DecoderBuffer>& buffer) {
+  CHECK_EQ(status, ::media::DemuxerStream::kOk);
+  CHECK(buffer.get());
+  CHECK(buffer_list);
+  buffer_list->push_back(new DecoderBufferAdapter(buffer));
+  base::MessageLoop::current()->QuitWhenIdle();

[damienv1, 2014/10/03 00:06:22]

I don't think that's the right location to call QuitWhenIdle (should not be done
in this file).
You should check with Sergey as to why it was done here (don't recall the
reason), but that does not belong logically to this file.

[servolk, 2014/10/03 00:24:57]

Well, the way it works at the moment is: in FFmpegDemuxForTest, instead of
creating a separate thread, we are just reusing the current thread for reading
from demuxer. We call stream->Read on line 334 and then call
MessageLoop::current()->Run on line 336, that blocks until we get a DemuxReadCB
and call QuitWhenIdle. I.e. this is just a way to convert asynchronous
DemuxerStream interface into synchronous FFmpegDemuxForTest API.

[gunsch, 2014/10/03 00:27:05]

Looks like using a RunLoop would be preferred to making explicit calls to
MessageLoop, at the very least. Separated it so it's only in the caller and not
here. Thoughts?

+}
+
+class FakeDemuxerHost : public ::media::DemuxerHost {
+ public:
+  // DemuxerHost implementation.
+  virtual void AddBufferedTimeRange(base::TimeDelta start,
+                                    base::TimeDelta end) OVERRIDE {}
+  virtual void SetDuration(base::TimeDelta duration) OVERRIDE {}
+  virtual void OnDemuxerError(::media::PipelineStatus error) OVERRIDE {
+    LOG(FATAL) << "OnDemuxerError: " << error;
+  }
+  virtual void AddTextStream(::media::DemuxerStream* text_stream,
+                             const ::media::TextTrackConfig& config) OVERRIDE {
+  }
+  virtual void RemoveTextStream(::media::DemuxerStream* text_stream) OVERRIDE {
+  }
+};
+
+DemuxResult::DemuxResult() {
+}
+
+DemuxResult::~DemuxResult() {
+}
+
+DemuxResult FFmpegDemuxForTest(const base::FilePath& filepath,
+                               bool audio) {
+  FakeDemuxerHost fake_demuxer_host;
+  ::media::FileDataSource data_source;
+  CHECK(data_source.Initialize(filepath));
+
+  ::media::FFmpegDemuxer demuxer(base::MessageLoopProxy::current(),
+                        &data_source,
+                        base::Bind(&FFDemuxNeedKeyCB),
+                        new ::media::MediaLog());
+  ::media::WaitableMessageLoopEvent init_event;
+  demuxer.Initialize(&fake_demuxer_host,
+                     init_event.GetPipelineStatusCB(),
+                     false);
+  init_event.RunAndWaitForStatus(::media::PIPELINE_OK);
+
+  ::media::DemuxerStream* stream = demuxer.GetStream(
+      audio ? ::media::DemuxerStream::AUDIO : ::media::DemuxerStream::VIDEO);
+  CHECK(stream);
+
+  DemuxResult demux_result;
+  if (audio) {
+    demux_result.audio_config = stream->audio_decoder_config();
+  } else {
+    demux_result.video_config = stream->video_decoder_config();
+  }
+
+  bool end_of_stream = false;
+  while (!end_of_stream) {
+    stream->Read(base::Bind(&DemuxReadCB,
+                            base::Unretained(&demux_result.frames)));
+    base::MessageLoop::current()->Run();
+    CHECK(!demux_result.frames.empty());
+    end_of_stream = demux_result.frames.back()->end_of_stream();
+  }
+
+  demuxer.Stop();
+  return demux_result;
+}
+
+}  // namespace media
+}  // namespace chromecast
+