CodecBoxDecoderContext(const char* filePath, CodecBoxDecoder& host_):
host(host_),
formatContext(nullptr),
videoStream(-1),
audioStream(-1),
videoCodecContext(nullptr),
audioCodecContext(nullptr),
sws(nullptr),
swr(nullptr),
decodedFrame(nullptr),
videoLineSize(0),
videoBuffer(nullptr),
audioBuffer(nullptr)
{
host.state = CodecBoxDecoderState::Init;
JIF(avformat_open_input(&formatContext, filePath, nullptr, nullptr) != 0,
"failed avformat_open_input: %s", filePath);
JIF(avformat_find_stream_info(formatContext, nullptr) < 0,
"failed avformat_find_stream_info: %s", filePath);
av_dump_format(formatContext, 0, filePath, 0);
host.duration = (double)formatContext->duration / AV_TIME_BASE;
host.startTime = (double)formatContext->start_time / AV_TIME_BASE;
for (int i = 0; i < formatContext->nb_streams; i++)
{
auto type = formatContext->streams[i]->codec->codec_type;
if (videoStream < 0 && type == AVMEDIA_TYPE_VIDEO) videoStream = i;
else if (audioStream < 0 && type == AVMEDIA_TYPE_AUDIO) audioStream = i;
}
JIF(videoStream < 0 && audioStream < 0 , "no audio/video stream found in %s", filePath);
if (videoStream >= 0)
{
videoCodecContext = createCodecContext(formatContext, videoStream);
JIF(videoCodecContext == nullptr, "video codec not supported");
host.hasVideo = true;
host.width = videoCodecContext->width;
host.height = videoCodecContext->height;
// videoCodecContext->framerate is usually not useful (0)
auto fr = formatContext->streams[videoStream]->avg_frame_rate;
host.frameRate = (double)fr.num / fr.den;
}
if (audioStream >= 0)
{
audioCodecContext = createCodecContext(formatContext, audioStream);
JIF(audioCodecContext == nullptr, "audio codec not supported");
host.hasAudio = true;
host.sampleRate = audioCodecContext->sample_rate;
host.channels = 2; // will be re-sampled as AV_CH_LAYOUT_STEREO. // audioCodecContext->channels;
}
decodedFrame = av_frame_alloc();
JIF(!decodedFrame, "faild to alloc decodedFrame");
host.state = CodecBoxDecoderState::Metadata;
return;
err:
host.state = CodecBoxDecoderState::Failed;
close();
}
bool VideoEncoder::init(const Desc& desc)
{
// Register the codecs
av_register_all();
// create the output context
avformat_alloc_output_context2(&mpOutputContext, nullptr, nullptr, mFilename.c_str());
if(mpOutputContext == nullptr)
{
// The sample tries again, while explicitly requesting mpeg format. I chose not to do it, since it might lead to a container with a wrong extension
return error(mFilename, "File output format not recognized. Make sure you use a known file extension (avi/mpeg/mp4)");
}
// Get the output format of the container
AVOutputFormat* pOutputFormat = mpOutputContext->oformat;
assert((pOutputFormat->flags & AVFMT_NOFILE) == 0); // Problem. We want a file.
// create the video codec
AVCodec* pVideoCodec;
mpOutputStream = createVideoStream(mpOutputContext, desc.fps, getCodecID(desc.codec), mFilename, pVideoCodec);
if(mpOutputStream == nullptr)
{
return false;
}
mpCodecContext = createCodecContext(mpOutputContext, desc.width, desc.height, desc.fps, desc.bitrateMbps, desc.gopSize, getCodecID(desc.codec), pVideoCodec);
if(mpCodecContext == nullptr)
{
return false;
}
// Open the video stream
if(openVideo(pVideoCodec, mpCodecContext, mpFrame, mFilename) == false)
{
return false;
}
// copy the stream parameters to the muxer
if(avcodec_parameters_from_context(mpOutputStream->codecpar, mpCodecContext) < 0)
{
return error(desc.filename, "Could not copy the stream parameters\n");
}
av_dump_format(mpOutputContext, 0, mFilename.c_str(), 1);
// Open the output file
assert((pOutputFormat->flags & AVFMT_NOFILE) == 0); // No output file required. Not sure if/when this happens.
if(avio_open(&mpOutputContext->pb, mFilename.c_str(), AVIO_FLAG_WRITE) < 0)
{
return error(mFilename, "Can't open output file.");
}
// Write the stream header
if(avformat_write_header(mpOutputContext, nullptr) < 0)
{
return error(mFilename, "Can't write file header.");
}
mFormat = desc.format;
mRowPitch = getFormatBytesPerBlock(desc.format) * desc.width;
if(desc.flipY)
{
mpFlippedImage = new uint8_t[desc.height * mRowPitch];
}
mpSwsContext = sws_getContext(desc.width, desc.height, getPictureFormatFromFalcorFormat(desc.format), desc.width, desc.height, mpCodecContext->pix_fmt, SWS_POINT, nullptr, nullptr, nullptr);
if(mpSwsContext == nullptr)
{
return error(mFilename, "Failed to allocate SWScale context");
}
return true;
}
