gecko-dev/content/media/fmp4/ffmpeg/FFmpegDataDecoder.cpp

125 lines
3.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include <string.h>
#include <unistd.h>
#include "MediaTaskQueue.h"
#include "mp4_demuxer/mp4_demuxer.h"
#include "FFmpegRuntimeLinker.h"
#include "FFmpegDataDecoder.h"
namespace mozilla
{
bool FFmpegDataDecoder::sFFmpegInitDone = false;
FFmpegDataDecoder::FFmpegDataDecoder(MediaTaskQueue* aTaskQueue,
AVCodecID aCodecID)
: mTaskQueue(aTaskQueue), mCodecID(aCodecID)
{
MOZ_COUNT_CTOR(FFmpegDataDecoder);
}
FFmpegDataDecoder::~FFmpegDataDecoder() {
MOZ_COUNT_DTOR(FFmpegDataDecoder);
}
/**
* FFmpeg calls back to this function with a list of pixel formats it supports.
* We choose a pixel format that we support and return it.
* For now, we just look for YUV420P as it is the only non-HW accelerated format
* supported by FFmpeg's H264 decoder.
*/
static PixelFormat
ChoosePixelFormat(AVCodecContext* aCodecContext, const PixelFormat* aFormats)
{
FFMPEG_LOG("Choosing FFmpeg pixel format for video decoding.");
for (; *aFormats > -1; aFormats++) {
if (*aFormats == PIX_FMT_YUV420P) {
FFMPEG_LOG("Requesting pixel format YUV420P.");
return PIX_FMT_YUV420P;
}
}
NS_WARNING("FFmpeg does not share any supported pixel formats.");
return PIX_FMT_NONE;
}
nsresult
FFmpegDataDecoder::Init()
{
FFMPEG_LOG("Initialising FFmpeg decoder.");
if (!FFmpegRuntimeLinker::Link()) {
NS_WARNING("Failed to link FFmpeg shared libraries.");
return NS_ERROR_FAILURE;
}
if (!sFFmpegInitDone) {
av_register_all();
#ifdef DEBUG
av_log_set_level(AV_LOG_DEBUG);
#endif
sFFmpegInitDone = true;
}
AVCodec* codec = avcodec_find_decoder(mCodecID);
if (!codec) {
NS_WARNING("Couldn't find ffmpeg decoder");
return NS_ERROR_FAILURE;
}
if (avcodec_get_context_defaults3(&mCodecContext, codec) < 0) {
NS_WARNING("Couldn't init ffmpeg context");
return NS_ERROR_FAILURE;
}
mCodecContext.opaque = this;
// FFmpeg takes this as a suggestion for what format to use for audio samples.
mCodecContext.request_sample_fmt = AV_SAMPLE_FMT_FLT;
// FFmpeg will call back to this to negotiate a video pixel format.
mCodecContext.get_format = ChoosePixelFormat;
AVDictionary* opts = nullptr;
if (avcodec_open2(&mCodecContext, codec, &opts) < 0) {
NS_WARNING("Couldn't initialise ffmpeg decoder");
return NS_ERROR_FAILURE;
}
if (mCodecContext.codec_type == AVMEDIA_TYPE_AUDIO &&
mCodecContext.sample_fmt != AV_SAMPLE_FMT_FLT &&
mCodecContext.sample_fmt != AV_SAMPLE_FMT_FLTP) {
NS_WARNING("FFmpeg AAC decoder outputs unsupported audio format.");
return NS_ERROR_FAILURE;
}
FFMPEG_LOG("FFmpeg init successful.");
return NS_OK;
}
nsresult
FFmpegDataDecoder::Flush()
{
mTaskQueue->Flush();
avcodec_flush_buffers(&mCodecContext);
return NS_OK;
}
nsresult
FFmpegDataDecoder::Shutdown()
{
if (sFFmpegInitDone) {
avcodec_close(&mCodecContext);
}
return NS_OK;
}
} // namespace mozilla