ffconv/ffcpp/MediaFile.cpp

108 lines
2.8 KiB
C++

#include "MediaFile.h"
#include "ffcpp.h"
#include <stdexcept>
namespace ffcpp {
MediaFile::MediaFile(const std::string& src, Mode mode) {
_mode = mode;
if(mode == Mode::Read) {
int res = avformat_open_input(&_formatCtx, src.c_str(), nullptr, nullptr);
throwIfError(res, "cannot open input file");
res = avformat_find_stream_info(_formatCtx, nullptr);
throwIfError(res, "cannot find stream info");
} else if(mode == Mode::Write) {
int res = avformat_alloc_output_context2(&_formatCtx, nullptr, nullptr, src.c_str());
throwIfError(res, "cannot allocate format context");
if (!(_formatCtx->oformat->flags & AVFMT_NOFILE)) {
res = avio_open(&_formatCtx->pb, src.c_str(), AVIO_FLAG_WRITE);
throwIfError(res, "cannot init avio context");
}
if(_formatCtx->oformat->flags & AVFMT_GLOBALHEADER)
_formatCtx->flags |= CODEC_FLAG_GLOBAL_HEADER;
av_dump_format(_formatCtx, 0, src.c_str(), 1);
}
}
bool MediaFile::hasStream(AVMediaType type) const {
for(size_t i = 0; i < _formatCtx->nb_streams; ++i) {
if(_formatCtx->streams[i]->codec->codec_type == type) {
return true;
}
}
return false;
}
bool MediaFile::hasVideo() const {
return hasStream(AVMEDIA_TYPE_VIDEO);
}
bool MediaFile::hasAudio() const {
return hasStream(AVMEDIA_TYPE_AUDIO);
}
Stream MediaFile::getStream(AVMediaType type, size_t index) const {
for(size_t i = 0, curIndex = 0; i < _formatCtx->nb_streams; ++i) {
if(_formatCtx->streams[i]->codec->codec_type == type) {
if(curIndex == index) {
return Stream(_formatCtx->streams[i]);
} else {
curIndex++;
}
}
}
throw std::runtime_error("cannot find stream");
}
Stream MediaFile::videoStream(size_t index /* = 0 */) const {
return getStream(AVMEDIA_TYPE_VIDEO, index);
}
Stream MediaFile::audioStream(size_t index /* = 0 */) const {
return getStream(AVMEDIA_TYPE_AUDIO, index);
}
MediaFile::operator AVFormatContext*() const {
return _formatCtx;
}
MediaFile::~MediaFile() {
if(_mode == Mode::Write) {
avformat_free_context(_formatCtx);
} else {
avformat_close_input(&_formatCtx);
}
}
Stream MediaFile::addStream(AVCodecID codecID, int width, int height, AVPixelFormat pixelFormat) {
AVCodec* codec = avcodec_find_encoder(codecID);
if(!codec) throw std::runtime_error("cannot find codec");
AVStream* stream = avformat_new_stream(_formatCtx, codec);
if(!stream) throw std::runtime_error("cannot create stream");
AVCodecContext* ctx = stream->codec;
ctx->width = width;
ctx->height = height;
ctx->pix_fmt = pixelFormat;
return Stream(stream, codec);
}
void MediaFile::writeHeader() {
int res = avformat_write_header(_formatCtx, nullptr);
throwIfError(res, "error writing header");
}
void MediaFile::writeTrailer() {
int res = av_write_trailer(_formatCtx);
throwIfError(res, "error writing trailer");
}
}