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media / filters / media_file_checker.cc [blame]
// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif
#include "media/filters/media_file_checker.h"
#include <stddef.h>
#include <stdint.h>
#include <map>
#include <memory>
#include <utility>
#include "base/functional/bind.h"
#include "base/time/time.h"
#include "media/ffmpeg/ffmpeg_common.h"
#include "media/ffmpeg/ffmpeg_decoding_loop.h"
#include "media/ffmpeg/ffmpeg_deleters.h"
#include "media/ffmpeg/scoped_av_packet.h"
#include "media/filters/blocking_url_protocol.h"
#include "media/filters/ffmpeg_glue.h"
#include "media/filters/file_data_source.h"
namespace media {
namespace {
constexpr int64_t kMaxCheckTimeInSeconds = 5;
void OnMediaFileCheckerError(bool* called) {
*called = false;
}
struct Decoder {
std::unique_ptr<AVCodecContext, ScopedPtrAVFreeContext> context;
std::unique_ptr<FFmpegDecodingLoop> loop;
};
} // namespace
MediaFileChecker::MediaFileChecker(base::File file) : file_(std::move(file)) {}
MediaFileChecker::~MediaFileChecker() = default;
bool MediaFileChecker::Start(base::TimeDelta check_time) {
media::FileDataSource source;
if (!source.Initialize(std::move(file_)))
return false;
bool read_ok = true;
media::BlockingUrlProtocol protocol(
&source, base::BindRepeating(&OnMediaFileCheckerError, &read_ok));
media::FFmpegGlue glue(&protocol);
AVFormatContext* format_context = glue.format_context();
if (!glue.OpenContext())
return false;
if (avformat_find_stream_info(format_context, NULL) < 0)
return false;
// Remember the codec context for any decodable audio or video streams.
bool found_streams = false;
std::vector<Decoder> stream_contexts(format_context->nb_streams);
for (size_t i = 0; i < format_context->nb_streams; ++i) {
AVCodecParameters* cp = format_context->streams[i]->codecpar;
if (cp->codec_type == AVMEDIA_TYPE_AUDIO ||
cp->codec_type == AVMEDIA_TYPE_VIDEO) {
auto context = AVStreamToAVCodecContext(format_context->streams[i]);
if (!context)
continue;
const AVCodec* codec = avcodec_find_decoder(cp->codec_id);
if (codec && avcodec_open2(context.get(), codec, nullptr) >= 0) {
auto loop = std::make_unique<FFmpegDecodingLoop>(context.get());
stream_contexts[i] = {std::move(context), std::move(loop)};
found_streams = true;
}
}
}
if (!found_streams)
return false;
auto packet = ScopedAVPacket::Allocate();
int result = 0;
auto do_nothing_cb = base::BindRepeating([](AVFrame*) { return true; });
const base::TimeTicks deadline =
base::TimeTicks::Now() +
std::min(check_time, base::Seconds(kMaxCheckTimeInSeconds));
do {
result = av_read_frame(glue.format_context(), packet.get());
if (result < 0)
break;
auto& decoder = stream_contexts[packet->stream_index];
if (decoder.loop) {
result = decoder.loop->DecodePacket(packet.get(), do_nothing_cb) ==
FFmpegDecodingLoop::DecodeStatus::kOkay
? 0
: -1;
}
av_packet_unref(packet.get());
} while (base::TimeTicks::Now() < deadline && read_ok && result >= 0);
stream_contexts.clear();
return read_ok && (result == AVERROR_EOF || result >= 0);
}
} // namespace media