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  • How to use ffmpeg to conver the mp3 with image to mp4 ?

    24 octobre 2012, par Ello

    the mp3 has image in it ,maybe some album images.when i use ffmpeg convert to mp4,it gone wrong.but if i use some mp3 without image,it succeed.

    My command is like this :

                       ffmpeg -i input.mp3 output.mp4

    error:

    Stream mapping:

      Stream #0:1 -> #0:0 (mjpeg -> mpeg4)

  Stream #0:0 -> #0:1 (mp3 -> aac)

    here is all console output:

    ellodeiMac:mine ello$ ffmpeg -frames 0 -i 4.mp3 -y test.mp4

ffmpeg version 0.11.2 Copyright (c) 2000-2012 the FFmpeg developers

  built on Oct 24 2012 12:21:13 with llvm_gcc 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.9.00)

  configuration: --disable-yasm

  libavutil      51. 54.100 / 51. 54.100

  libavcodec     54. 23.100 / 54. 23.100

  libavformat    54.  6.100 / 54.  6.100

  libavdevice    54.  0.100 / 54.  0.100

  libavfilter     2. 77.100 /  2. 77.100

  libswscale      2.  1.100 /  2.  1.100

  libswresample   0. 15.100 /  0. 15.100

[mp3 @ 0x7fa12301ae00] max_analyze_duration 5000000 reached at 5015510
Input #0, mp3, from '4.mp3':

  Metadata:

    artist          : 贵族乐团

    album           : 美声天籁

    title           : 肖邦离别曲

    Tagging time    : 2012-09-18T08:12:10

  Duration: 00:04:01.44, start: 0.000000, bitrate: 129 kb/s

    Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16, 128 kb/s

    Stream #0:1: Video: mjpeg, yuvj420p, 240x240 [SAR 1:1 DAR 1:1], 90k tbr, 90k tbn, 90k tbc

    Metadata:

      title           : e

      comment         : Cover (front)

[buffer @ 0x109115780] w:240 h:240 pixfmt:yuvj420p tb:1/90000 sar:1/1 sws_param:flags=2

[buffersink @ 0x109133720] No opaque field provided

[format @ 0x1091338e0] auto-inserting filter 'auto-inserted scaler 0' between the filter 'src' and the filter 'format'

[scale @ 0x109133bc0] w:240 h:240 fmt:yuvj420p sar:1/1 -> w:240 h:240 fmt:yuv420p sar:1/1 flags:0x4

[mp4 @ 0x7fa123035c00] Frame rate very high for a muxer not efficiently supporting it.

Please consider specifying a lower framerate, a different muxer or -vsync 2

[aformat @ 0x109136ec0] auto-inserting filter 'auto-inserted resampler 0' between the filter 'src' and the filter 'aformat'

[aresample @ 0x1091370c0] chl:stereo fmt:s16 r:44100Hz -> chl:stereo fmt:flt r:44100Hz

[mpeg4 @ 0x7fa12303be00] timebase 1/90000 not supported by MPEG 4 standard, the maximum 
admitted value for the timebase denominator is 65535

Output #0, mp4, to 'test.mp4':

  Metadata:

    artist          : 贵族乐团

    album           : 美声天籁

    title           : 肖邦离别曲

    Tagging time    : 2012-09-18T08:12:10

    Stream #0:0: Video: mpeg4, yuv420p, 240x240 [SAR 1:1 DAR 1:1], q=2-31, 200 kb/s, 90k tbn, 90k tbc

    Metadata:

      title           : e

      comment         : Cover (front)

    Stream #0:1: Audio: none, 44100 Hz, stereo, flt, 128 kb/s

Stream mapping:

  Stream #0:1 -> #0:0 (mjpeg -> mpeg4)

  Stream #0:0 -> #0:1 (mp3 -> aac)

Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height

  • ffmpeg frame grabbing slow on mp4 files

    24 octobre 2012, par user1444886

    The following ffmpeg frame grab command takes a long time to grab an image from the mp4 file.

    ffmpeg.exe -itsoffset -200 -i C:\93844428.mp4 -vcodec mjpeg -vframes 1 -y -an -f rawvideo -s 640x360 C:\test\out1.jpg

    For a 20MB file (about 2 minutes of video) it takes up to about 6 seconds to find the image depending on what offset (in seconds) you ask to grab it.

    For a 100MB it can anything in many minutes if you request a large offset.

    This only appears to be an issue with mp4 files.

    Is there anything that can be done to improve this?

  • Cannot get libav custom IO to work for jpg image file

    24 octobre 2012, par Bloodwolf

    I am trying to create a custom input stream. However, avformat_open_input fails with a random error value. I would appreciate it if someone can tell me what is it that I am doing wrong. Here is the simplified code.

    Thank you in advance for your help.

    #define BUFSIZE (4 * 1024)

static int ReadPacket(void* opaque, uint8_t* buf, int bufsize) 
{
    FILE* file = (FILE*) opaque;

    int len = fread(buf, 1, bufsize, file);
    return len;
}


int main(int argc, char* argv[]) 
{

    av_register_all();
    // av_log_set_level(AV_LOG_DEBUG);

    const char* fileName = "/home/alan/sample.jpg";
    FILE* file = fopen(fileName, "rb");

    unsigned char* buffer = (unsigned char*) av_malloc(BUFSIZE);

    AVIOContext* avContext = avio_alloc_context(buffer, BUFSIZE, 1, file,ReadPacket, NULL, NULL);

    AVFormatContext* pFormatCtx = avformat_alloc_context();
    pFormatCtx->pb = avContext;

    int val = avformat_open_input(&pFormatCtx, fileName, NULL, NULL);
    if (val != 0) 
    {
        printf("Open input failed. Err: %d\n", val);
        pFormatCtx = 0; // it is already freed
        av_free(avContext);
        av_free(buffer);
        fclose(file);
        return -1;
    }
}

    But if I replace the fileName by "/home/alan/demo.avi", it works..

  • FFmpeg : Jpeg file to AVFrame

    24 octobre 2012, par darja

    I need to join several jpg files into video using FFmpeg library. But I have a problem with reading this files. Here is a function which reads image file and makes AVFrame:

    AVFrame* OpenImage(const char* imageFileName)
{
    AVFormatContext *pFormatCtx;

    if(av_open_input_file(&pFormatCtx, imageFileName, NULL, 0, NULL)!=0)
    {
        printf("Can't open image file '%s'\n", imageFileName);
        return NULL;
    }       

    dump_format(pFormatCtx, 0, imageFileName, false);

    AVCodecContext *pCodecCtx;

    pCodecCtx = pFormatCtx->streams[0]->codec;
    pCodecCtx->width = W_VIDEO;
    pCodecCtx->height = H_VIDEO;
    pCodecCtx->pix_fmt = PIX_FMT_YUV420P;

    // Find the decoder for the video stream
    AVCodec *pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
    if (!pCodec)
    {
        printf("Codec not found\n");
        return NULL;
    }

    // Open codec
    if(avcodec_open(pCodecCtx, pCodec)<0)
    {
        printf("Could not open codec\n");
        return NULL;
    }

    // 
    AVFrame *pFrame;

    pFrame = avcodec_alloc_frame();

    if (!pFrame)
    {
        printf("Can't allocate memory for AVFrame\n");
        return NULL;
    }

    int frameFinished;
    int numBytes;

    // Determine required buffer size and allocate buffer
    numBytes = avpicture_get_size(PIX_FMT_YUVJ420P, pCodecCtx->width, pCodecCtx->height);
    uint8_t *buffer = (uint8_t *) av_malloc(numBytes * sizeof(uint8_t));

    avpicture_fill((AVPicture *) pFrame, buffer, PIX_FMT_YUVJ420P, pCodecCtx->width, pCodecCtx->height);

    // Read frame

    AVPacket packet;

    int framesNumber = 0;
    while (av_read_frame(pFormatCtx, &packet) >= 0)
    {
        if(packet.stream_index != 0)
            continue;

        int ret = avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
        if (ret > 0)
        {
            printf("Frame is decoded, size %d\n", ret);
            pFrame->quality = 4;
            return pFrame;
        }
        else
            printf("Error [%d] while decoding frame: %s\n", ret, strerror(AVERROR(ret)));
    }
}

    This causes no error but creates only black frame, no image. What is wrong?

  • How do I subtract a word from the output in bash

    23 octobre 2012, par user1768840

    I made a simple bash script to convert movies from .avi to .mp4 but now I want to do two more things.

    1. Have the output file have only *.mp4 rather than *.avi.mp4
    2. Delete the old file after the conversion is completed.

    Here is my script.

    #!/bin/bash


avconv -i "$1" -c:v libx264 -c:a copy -sn -crf 24 "$1".mp4

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