我需要使用自己的ioContext将任何格式（例如mp4，avi等）转换为.webm。我用vpx，ogg，vorbis，opus构建ffmpeg并创建简单的项目。但是当我写任何帧时，我收到错误消息“太多看不见的帧。无法发送数据包来过滤流0的vp9_superframe”
我已经尝试使用具有avcodec_parameters_copy的复制编解码器参数从webm转换为webm，并且可以正常工作。
#include <QCoreApplication>
#include <QFileInfo>
#include <iostream>
#include <fstream>
extern "C" {
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavutil/timestamp.h>
#include <libavformat/avformat.h>
#include <libavfilter/buffersink.h>
#include <libavfilter/buffersrc.h>
#include <libavutil/opt.h>
#include <libavutil/pixdesc.h>
}
using namespace std;
struct BufferData {
QByteArray data;
uint fullsize;
BufferData() {
fullsize =0;
}
};
static int write_packet_to_buffer(void *opaque, uint8_t *buf, int buf_size) {
BufferData *bufferData = static_cast<BufferData*>(opaque);
bufferData->fullsize += buf_size;
bufferData->data.append((const char*)buf, buf_size);
return buf_size;
}
static bool writeBuffer(const QString &filename, BufferData *bufferData) {
QFile file(filename);
if( !file.open(QIODevice::WriteOnly) ) return false;
file.write(bufferData->data);
qDebug()<<"FILE SIZE = " << file.size();
file.close();
return true;
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
AVOutputFormat *ofmt = NULL;
AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
AVPacket pkt;
int ret;
int stream_index = 0;
int *stream_mapping = NULL;
int stream_mapping_size = 0;
const char *in_filename = "../assets/sample.mp4";
const char *out_filename = "../assets/sample_new.webm";
//------------------------ Input file ----------------------------
if ((ret = avformat_open_input(&ifmt_ctx, in_filename, 0, 0)) < 0) {
fprintf(stderr, "Could not open input file '%s'", in_filename);
return 1;
}
if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) < 0) {
fprintf(stderr, "Failed to retrieve input stream information");
return 1;
}
av_dump_format(ifmt_ctx, 0, in_filename, 0);
//-----------------------------------------------------------------
//---------------------- BUFFER -------------------------
AVIOContext *avio_ctx = NULL;
uint8_t *avio_ctx_buffer = NULL;
size_t avio_ctx_buffer_size = 4096*1024;
const size_t bd_buf_size = 1024*1024;
/* fill opaque structure used by the AVIOContext write callback */
avio_ctx_buffer = (uint8_t*)av_malloc(avio_ctx_buffer_size);
if (!avio_ctx_buffer) return AVERROR(ENOMEM);
BufferData bufferData;
avio_ctx = avio_alloc_context(avio_ctx_buffer, avio_ctx_buffer_size,
1, &bufferData, NULL,
&write_packet_to_buffer, NULL);
if (!avio_ctx) return AVERROR(ENOMEM);
//------------------------------------------------------
avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, out_filename);
if (!ofmt_ctx) {
fprintf(stderr, "Could not create output context\n");
ret = AVERROR_UNKNOWN;
return 1;
}
//------------------------ Stream list ----------------------------
stream_mapping_size = ifmt_ctx->nb_streams;
stream_mapping = (int*)av_mallocz_array(stream_mapping_size, sizeof(*stream_mapping));
if (!stream_mapping) {
ret = AVERROR(ENOMEM);
return 1;
}
//-------------------------------------------------------------------
//------------------------ Output file ----------------------------
AVCodec *encoder;
AVCodecContext *input_ctx;
AVCodecContext *enc_ctx;
for (int i=0; i < ifmt_ctx->nb_streams; i++) {
AVStream *out_stream;
AVStream *in_stream = ifmt_ctx->streams[i];
AVCodecParameters *in_codecpar = in_stream->codecpar;
if (in_codecpar->codec_type != AVMEDIA_TYPE_AUDIO &&
in_codecpar->codec_type != AVMEDIA_TYPE_VIDEO &&
in_codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE) {
stream_mapping[i] = -1;
continue;
}
enc_ctx = avcodec_alloc_context3(encoder);
if (!enc_ctx) {
av_log(NULL, AV_LOG_FATAL, "Failed to allocate the encoder context\n");
return AVERROR(ENOMEM);
}
stream_mapping[i] = stream_index++;
out_stream = avformat_new_stream(ofmt_ctx, NULL);
if (!out_stream) {
fprintf(stderr, "Failed allocating output stream\n");
ret = AVERROR_UNKNOWN;
return 1;
}
out_stream->codecpar->width = in_codecpar->width;
out_stream->codecpar->height = in_codecpar->height;
out_stream->codecpar->level = in_codecpar->level;
out_stream->codecpar->format =in_codecpar->format;
out_stream->codecpar->profile =in_codecpar->profile;
out_stream->codecpar->bit_rate =in_codecpar->bit_rate;
out_stream->codecpar->channels =in_codecpar->channels;
out_stream->codecpar->codec_tag = 0;
out_stream->codecpar->color_trc =in_codecpar->color_trc;
out_stream->codecpar->codec_type =in_codecpar->codec_type;
out_stream->codecpar->frame_size =in_codecpar->frame_size;
out_stream->codecpar->block_align =in_codecpar->block_align;
out_stream->codecpar->color_range =in_codecpar->color_range;
out_stream->codecpar->color_space =in_codecpar->color_space;
out_stream->codecpar->field_order =in_codecpar->field_order;
out_stream->codecpar->sample_rate =in_codecpar->sample_rate;
out_stream->codecpar->video_delay =in_codecpar->video_delay;
out_stream->codecpar->seek_preroll =in_codecpar->seek_preroll;
out_stream->codecpar->channel_layout =in_codecpar->channel_layout;
out_stream->codecpar->chroma_location =in_codecpar->chroma_location;
out_stream->codecpar->color_primaries =in_codecpar->color_primaries;
out_stream->codecpar->initial_padding =in_codecpar->initial_padding;
out_stream->codecpar->trailing_padding =in_codecpar->trailing_padding;
out_stream->codecpar->bits_per_raw_sample = in_codecpar->bits_per_raw_sample;
out_stream->codecpar->sample_aspect_ratio.num = in_codecpar->sample_aspect_ratio.num;
out_stream->codecpar->sample_aspect_ratio.den = in_codecpar->sample_aspect_ratio.den;
out_stream->codecpar->bits_per_coded_sample = in_codecpar->bits_per_coded_sample;
if (in_codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
out_stream->codecpar->codec_id =ofmt_ctx->oformat->video_codec;
}
else if(in_codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
out_stream->codecpar->codec_id = ofmt_ctx->oformat- >audio_codec;
}
}
av_dump_format(ofmt_ctx, 0, out_filename, 1);
ofmt_ctx->pb = avio_ctx;
ret = avformat_write_header(ofmt_ctx, NULL);
if (ret < 0) {
fprintf(stderr, "Error occurred when opening output file\n");
return 1;
}
//------------------------------------------------------------------------------
while (1) {
AVStream *in_stream, *out_stream;
ret = av_read_frame(ifmt_ctx, &pkt);
if (ret < 0)
break;
in_stream = ifmt_ctx->streams[pkt.stream_index];
if (pkt.stream_index >= stream_mapping_size ||
stream_mapping[pkt.stream_index] < 0) {
av_packet_unref(&pkt);
continue;
}
pkt.stream_index = stream_mapping[pkt.stream_index];
out_stream = ofmt_ctx->streams[pkt.stream_index];
/* copy packet */
pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, AVRounding(AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));
pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, AVRounding(AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));
pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);
pkt.pos = -1;
ret = av_interleaved_write_frame(ofmt_ctx, &pkt);
if (ret < 0) {
fprintf(stderr, "Error muxing packet\n");
break;
}
av_packet_unref(&pkt);
}
av_write_trailer(ofmt_ctx);
avformat_close_input(&ifmt_ctx);
/* close output */
writeBuffer(fileNameOut, &bufferData);
avformat_free_context(ofmt_ctx);
av_freep(&stream_mapping);
if (ret < 0 && ret != AVERROR_EOF) {
fprintf(stderr, "Error occurred: %d\n",ret);
return 1;
}
return a.exec();
}