I am new to ffmpeg and I tried using api-example.c to decode wma files. However, when I run the program, it gave me an error saying
"frame_len overflow". Does anyone know how to fix this error?
Here is my code:
extern "C" { #include <avcodec.h> #include "../libavcodec/avcodec.h" #include <avformat.h> } #include <iostream> #include <assert.h> #include <windows.h> #include <mmsystem.h> #define INBUF_SIZE 4096 #define AUDIO_INBUF_SIZE 20480 #define AUDIO_REFILL_THRESH 4096 int main(int argc, char *argv[]) { avcodec_init(); avcodec_register_all(); //avdevice_register_all(); av_register_all(); AVCodec *codec; AVCodecContext *c= NULL; AVCodec *ocodec; AVCodecContext *oc= NULL; int out_size, len,out_size2; FILE *f, *outfile; uint8_t *outbuf; uint8_t inbuf[AUDIO_INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; AVPacket avpkt; char* outfilename="test.wma"; char* filename="Beethoven's.wma"; AVFormatContext *pFormatCtx; WAVEFORMATEX* wfx=new WAVEFORMATEX; int ret; ret=av_open_input_file(&pFormatCtx, filename, NULL, 0, NULL); if(ret!=0) { std::cout<<"cannot open file!"<<std::endl; exit(1); } if(av_find_stream_info(pFormatCtx)<0) { std::cout<<"cannot find stream!"<<std::endl; exit(1); } int audioStream; AVCodecContext *pCodecCtx; // Find the first video stream audioStream=-1; for(int i=0; i<pFormatCtx->nb_streams; i++) if(pFormatCtx->streams[i]->codec->codec_type==CODEC_TYPE_AUDIO) { audioStream=i; break; } if(audioStream==-1) { std::cout<<"cannot find audio!"<<std::endl; } // Get a pointer to the codec context for the audio stream pCodecCtx=pFormatCtx->streams[audioStream]->codec; av_init_packet(&avpkt); printf("Audio decoding\n"); /* find the suitable audio decoder */ codec = avcodec_find_decoder(pCodecCtx->codec_id); if (!codec) { fprintf(stderr, "codec not found\n"); exit(1); } if(codec->capabilities & CODEC_CAP_TRUNCATED) pCodecCtx->flags|=CODEC_FLAG_TRUNCATED; //open the codec (for decoding) int test = avcodec_open(pCodecCtx, codec); if (test < 0) { fprintf(stderr, "could not open codec\n"); exit(1); } //find mp3 encoder ocodec = avcodec_find_encoder(CODEC_ID_MP3); if (!ocodec) { fprintf(stderr, "codec not found\n"); exit(1); } //allocate context oc= avcodec_alloc_context(); /* put sample parameters */ oc->bit_rate = 64000; oc->sample_rate = 44100; oc->channels = 1; /* open it */ if (avcodec_open(oc, ocodec) < 0) { fprintf(stderr, "could not open encoding codec\n"); exit(1); } //buffer outbuf = (uint8_t*)malloc(AVCODEC_MAX_AUDIO_FRAME_SIZE); //open inputfile f = fopen(filename, "rb"); if (!f) { fprintf(stderr, "could not open %s\n", filename); exit(1); } //open outputfile outfile = fopen(outfilename, "wb"); if (!outfile) { av_free(c); exit(1); } /* decode until eof */ avpkt.data = inbuf; avpkt.size = fread(inbuf, 1, AUDIO_INBUF_SIZE, f); //while there is still data while (avpkt.size > 0) { std::cout<<"decoding..."<<std::endl; out_size = AVCODEC_MAX_AUDIO_FRAME_SIZE; //decode len = avcodec_decode_audio3(pCodecCtx, (short *)outbuf, &out_size, &avpkt); if (len < 0) { fprintf(stderr, "Error while decoding\n"); exit(1); } if (out_size > 0) { /* if a frame has been decoded, output it */ std::cout<<"1 frame decoded!"<<std::endl; out_size2 = avcodec_encode_audio(oc, outbuf, out_size, (short*)outbuf); fwrite(outbuf, 1, out_size2, outfile); } //subtract data from whatever decode function returns avpkt.size -= len; avpkt.data += len; if (avpkt.size < AUDIO_REFILL_THRESH) { /* Refill the input buffer, to avoid trying to decode * incomplete frames. Instead of this, one could also use * a parser, or use a proper container format through * libavformat. */ memmove(inbuf, avpkt.data, avpkt.size); avpkt.data = inbuf; len = fread(avpkt.data + avpkt.size, 1, AUDIO_INBUF_SIZE - avpkt.size, f); if (len > 0) avpkt.size += len; } } fclose(outfile); fclose(f); free(outbuf); avcodec_close(c); av_free(c); }
I have been stuck with this for quite some time. Please help me. Does anyone know what is wrong with my code?
Thanks,
Izak