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Sur d’autres sites (10591)

  • how to decode wmp3 video using libavcodec ? (ffmpeg)

    13 mars 2012, par Renan Elias

    I'm developing an application that reads a live tv stream from the internet and I need to play it on my ipad application.

    I've compiled the ffmpeg into my ipad application to use the libavcodec lib, but I've not been able to use it in this lib...

    I know how to get the stream packets, read if it is an audio or video packet, but I don't know how to use the lib to convert the original packet codecs to h264 and mp3 codec...

    I need to convert an stream packet wmv3 to h264 and save it on a file.

    My code is below...

    AVFormatContext* pFormatCtx = avformat_alloc_context();
    
int             i, videoStream, audioStream;
    
AVCodecContext  *pCodecCtx;
    
AVCodecContext *aCodecCtx;
    
AVCodec         *pCodec;
    
AVCodec         *aCodec;
    
AVFrame         *pFrame; 
    
AVFrame         *pFrameRGB;
    
AVPacket        packet;
    
int             frameFinished;
    
int             numBytes;
    
uint8_t         *buffer;
    

    
static struct SwsContext *img_convert_ctx;
    

    

    
// Register all formats and codecs
    
av_register_all();
    
avcodec_register_all();
    
avformat_network_init();
    

    
// Open video file
    
if(avformat_open_input(&pFormatCtx, [objURL cStringUsingEncoding:NSASCIIStringEncoding] ,NULL,NULL) != 0){
    
    return -1;
    
}
    

    
// Retrieve stream information
    
if(avformat_find_stream_info(pFormatCtx, NULL)<0)
    
    return -1; // Couldn't find stream information
    

    
// Dump information about file onto standard error
    
av_dump_format(pFormatCtx, 0, [objURL cStringUsingEncoding:NSASCIIStringEncoding], 0);
    

    
// Find the first video stream
    
videoStream=-1;
    
audioStream=-1;
    
for(i=0; i < pFormatCtx->nb_streams; i++) {
    
    if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO && videoStream < 0) {
    
        videoStream=i;
    
    }
    
    if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO && audioStream < 0) {
    
        audioStream=i;
    
    }
    
}
    
if(videoStream==-1)
    
    return -1; // Didn't find a video stream
    
if(audioStream==-1)
    
    return -1;
    

    
// Get a pointer to the codec context for the video stream
    
pCodecCtx=pFormatCtx->streams[videoStream]->codec;
    

    
// Find the decoder for the video stream
    
pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
    
if(pCodec==NULL) {
    
    fprintf(stderr, "Unsupported codec!\n");
    
    return -1; // Codec not found
    
}
    

    
// Open codec
    
if(avcodec_open2(pCodecCtx, pCodec, NULL)<0)
    
    return -1; // Could not open codec
    

    
// Get a pointer to the codec context for the audio stream
    
aCodecCtx=pFormatCtx->streams[audioStream]->codec;
    

    
// Find the decoder for the audio stream
    
aCodec = avcodec_find_decoder(aCodecCtx->codec_id);
    
if(!aCodec) {
    
    fprintf(stderr, "Unsupported codec!\n");
    
    return -1; // Codec not found
    
}
    

    
// Open codec
    
if(avcodec_open2(aCodecCtx, aCodec, NULL)<0)
    
    return -1; // Could not open codec
    

    
// Allocate video frame
    
pFrame=avcodec_alloc_frame();
    

    
// Allocate an AVFrame structure
    
pFrameRGB=avcodec_alloc_frame();
    
if(pFrameRGB==NULL)
    
    return -1;
    

    
// Determine required buffer size and allocate buffer
    
numBytes=avpicture_get_size(PIX_FMT_RGB24, pCodecCtx->width,
    
                            pCodecCtx->height);
    
buffer=(uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
    

    
// Assign appropriate parts of buffer to image planes in pFrameRGB
    
// Note that pFrameRGB is an AVFrame, but AVFrame is a superset
    
// of AVPicture
    
avpicture_fill((AVPicture *)pFrameRGB, buffer, PIX_FMT_RGB24,
    
               pCodecCtx->width, pCodecCtx->height);
    

    
// Read frames and save first five frames to disk
    
i=0;
    
while(av_read_frame(pFormatCtx, &packet)>=0) {
    
    // Is this a packet from the video stream?
    
    if(packet.stream_index==audioStream) {
    
        NSLog(@"Audio.. i'll solve the video first...");
    
    } else if(packet.stream_index==videoStream) {
    

    
        /// HOW CONVERT THIS VIDEO PACKET TO H264 and save on a file? :(
    
    }
    

    
    // Free the packet that was allocated by av_read_frame
    
    av_free_packet(&packet);
    
}
    

    
// Free the RGB image
    
av_free(buffer);
    
av_free(pFrameRGB);
    

    
// Free the YUV frame
    
av_free(pFrame);
    

    
// Close the codec
    
avcodec_close(pCodecCtx);
    

    
// Close the video file
    
avformat_close_input(&pFormatCtx);
    

    
return 0;

  • ffmpeg says : "option framerate not found"

    16 juillet 2013, par Jason

    Good afternoon.

    I've been trying to use ffmpeg to split a .mpeg into a sequence of .jpeg images. Please note that this is the inverse problem of the one specified here, but the problem I'm facing is not the same as the problem the author of that thread is facing.

    Specifically, I have tried all the following mpeg codecs available in my ffmpeg installation :

    DEV D  ffv1            FFmpeg video codec #1
    
DEVSD  ffvhuff         Huffyuv FFmpeg variant
    
DEVSDT mpeg1video      MPEG-1 video
    
D V DT mpeg1video_vdpau MPEG-1 video (VDPAU acceleration)
    
D V D  mpeg2_crystalhd MPEG-2 Video (CrystalHD acceleration)
    
DEVSDT mpeg2video      MPEG-2 video
    
DEVSDT mpeg4           MPEG-4 part 2
    
D V D  mpeg4_crystalhd MPEG-4 Part 2 (CrystalHD acceleration)
    
D V DT mpeg4_vdpau     MPEG-4 part 2 (VDPAU)
    
D VSDT mpegvideo       MPEG-1 video
    
D V DT mpegvideo_vdpau MPEG-1/2 video (VDPAU acceleration)
    
D VSDT mpegvideo_xvmc  MPEG-1/2 video XvMC (X-Video Motion Compensation)
    
DEVSD  msmpeg4         MPEG-4 part 2 Microsoft variant version 3
    
D V D  msmpeg4_crystalhd MPEG-4 Part 2 Microsoft variant version 3 (CrystalHD acceleration)
    
D VSD  msmpeg4v1       MPEG-4 part 2 Microsoft variant version 1
    
DEVSD  msmpeg4v2       MPEG-4 part 2 Microsoft variant version 2

    I've tried supplying ffmpeg with all different codecs to try to split an input .mpeg video file with 2548 frames into 2548 .jpegs, by using the -vcodec option :

    ffmpeg -r 2548 -i frames.mpeg frames_%06d.jpg -vcodec $codec

    where $codec is any codec among the ones listed above, e.g. ffv1, mpeg4, etc. However, all my efforts result in the following error :

    [NULL @ 0x1948f20] Value 4707126720094797824.000000 for parameter 'probesize' out of range
    
[NULL @ 0x1948f20] Value 4707126720094797824.000000 for parameter 'analyzeduration' out of range
    
[NULL @ 0x1948f20] Value 4697254411347427328.000000 for parameter 'indexmem' out of range
    
[NULL @ 0x1948f20] Value 4703785510416416768.000000 for parameter 'rtbufsize' out of range
    
[NULL @ 0x1948f20] Value -4616189618054758400.000000 for parameter 'fpsprobesize' out of range
    
[NULL @ 0x1948f20] Value 4607182418800017408.000000 for parameter 'f_err_detect' out of     range
    
[NULL @ 0x1948f20] Value 4607182418800017408.000000 for parameter 'err_detect' out of range
    
Option framerate not found.  

    Which is weird, because I've actually specified the frame rate parameter through the -r switch. I googled a bit and it appears that this error was mentioned approximately a year and a half ago on the ffmpeg bug tracker but that information makes little sense to me because it's relevant to the devs. Curiously, if I interchange the position of the parameters and put -r after -i or even after -vcodec, the error message changes to :

    [NULL @ 0x24abf20] Value 4707126720094797824.000000 for parameter 'probesize' out of range
    
[NULL @ 0x24abf20] Value 4707126720094797824.000000 for parameter 'analyzeduration' out of range
    
[NULL @ 0x24abf20] Value 4697254411347427328.000000 for parameter 'indexmem' out of range
    
[NULL @ 0x24abf20] Value 4703785510416416768.000000 for parameter 'rtbufsize' out of range
    
[NULL @ 0x24abf20] Value -4616189618054758400.000000 for parameter 'fpsprobesize' out of  range
    
[NULL @ 0x24abf20] Value 4607182418800017408.000000 for parameter 'f_err_detect' out of  range
    
[NULL @ 0x24abf20] Value 4607182418800017408.000000 for parameter 'err_detect' out of range
    
[NULL @ 0x24b23c0] Value 4686111960511545344.000000 for parameter 'b' out of range
    
[NULL @ 0x24b23c0] Value 4683532506232782848.000000 for parameter 'ab' out of range
    
[NULL @ 0x24b23c0] Value 4705844345939427328.000000 for parameter 'bt' out of range
    
[NULL @ 0x24b23c0] Value 4617315517961601024.000000 for parameter 'me_method' out of range
    
[NULL @ 0x24b23c0] Value 4622945017495814144.000000 for parameter 'g' out of range
    
[NULL @ 0x24b23c0] Value 4611686018427387904.000000 for parameter 'qmin' out of range
    
[NULL @ 0x24b23c0] Value 4629418941960159232.000000 for parameter 'qmax' out of range
    
[NULL @ 0x24b23c0] Value 4613937818241073152.000000 for parameter 'qdiff' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'wpredp' out of range
    
[NULL @ 0x24b23c0] Value 4607182418800017408.000000 for parameter 'bug' out of range
    
[NULL @ 0x24b23c0] Value 4607182418800017408.000000 for parameter 'er' out of range
    
[NULL @ 0x24b23c0] Value 4607182418800017408.000000 for parameter 'err_detect' out of range
    
[NULL @ 0x24b23c0] Value 4613937818241073152.000000 for parameter 'ec' out of range
    
[NULL @ 0x24b23c0] Value 4620693217682128896.000000 for parameter 'ildctcmp' out of range
    
[NULL @ 0x24b23c0] Value 4620693217682128896.000000 for parameter 'subq' out of range
    
[NULL @ 0x24b23c0] Value 4696837138094751744.000000 for parameter 'ibias' out of range
    
[NULL @ 0x24b23c0] Value 4696837138094751744.000000 for parameter 'pbias' out of range
    
[NULL @ 0x24b23c0] Value 4642507528377204736.000000 for parameter 'lmin' out of range
    
[NULL @ 0x24b23c0] Value 4660262442142531584.000000 for parameter 'lmax' out of range
    
[NULL @ 0x24b23c0] Value 4696130710463840256.000000 for parameter 'flags2' out of range
    
[NULL @ 0x24b23c0] Value 4607182418800017408.000000 for parameter 'threads' out of range
    
[NULL @ 0x24b23c0] Value 4620693217682128896.000000 for parameter 'nssew' out of range
    
[NULL @ 0x24b23c0] Value -4586705114244317184.000000 for parameter 'profile' out of range
    
[NULL @ 0x24b23c0] Value -4586705114244317184.000000 for parameter 'level' out of range
    
[NULL @ 0x24b23c0] Value 4623507967449235456.000000 for parameter 'skipcmp' out of range
    
[NULL @ 0x24b23c0] Value 4642507528377204736.000000 for parameter 'mblmin' out of range
    
[NULL @ 0x24b23c0] Value 4660262442142531584.000000 for parameter 'mblmax' out of range
    
[NULL @ 0x24b23c0] Value 4643211215818981376.000000 for parameter 'mepc' out of range
    
[NULL @ 0x24b23c0] Value 4607182418800017408.000000 for parameter 'bidir_refine' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'cqp' out of range
    
[NULL @ 0x24b23c0] Value 4627730092099895296.000000 for parameter 'keyint_min' out of range
    
[NULL @ 0x24b23c0] Value 4607182418800017408.000000 for parameter 'refs' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'directpred' out of range
    
[NULL @ 0x24b23c0] Value 4618441417868443648.000000 for parameter 'sc_factor' out of range
    
[NULL @ 0x24b23c0] Value 4643211215818981376.000000 for parameter 'mv0_threshold' out of range
    
[NULL @ 0x24b23c0] Value 4630826316843712512.000000 for parameter 'b_sensitivity' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'compression_level' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'min_prediction_order' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'max_prediction_order' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'prediction_order_method' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'min_partition_order' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'max_partition_order' out of range
    
[NULL @ 0x24b23c0] Value 4607182418800017408.000000 for parameter 'ticks_per_frame' out of range
    
[NULL @ 0x24b23c0] Value 4611686018427387904.000000 for parameter 'color_primaries' out of range
    
[NULL @ 0x24b23c0] Value 4611686018427387904.000000 for parameter 'color_trc' out of range
    
[NULL @ 0x24b23c0] Value 4611686018427387904.000000 for parameter 'colorspace' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'aq_mode' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'rc_lookahead' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'lpc_type' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'lpc_passes' out of range
    
[NULL @ 0x24b23c0] Value 4613937818241073152.000000 for parameter 'thread_type' out of range
    
[NULL @ 0x24b23c0] Value -4616189618054758400.000000 for parameter 'request_sample_fmt' out of range
    
frames.mpeg: could not find codec parameters

    I'm at a loss as to what to do with this problem, and am looking for some assistance.

    Kind regards,

    Jason

  • iPhone - A problem with decoding H264 using ffmpeg

    25 mars 2012, par HAPPY_TIGER

    I am working with ffmpeg to decode H264 stream from server.

    I referenced DecoderWrapper from http://github.com/dropcam/dropcam_for_iphone.

    I compiled it successfully, but I don't know how use it.

    Here are the function that has problem.

    - (id)initWithCodec:(enum VideoCodecType)codecType 
    
         colorSpace:(enum VideoColorSpace)colorSpace 
    
              width:(int)width 
    
             height:(int)height 
    
        privateData:(NSData*)privateData {
    
    if(self = [super init]) {
    

    
        codec = avcodec_find_decoder(CODEC_ID_H264);
    
        codecCtx = avcodec_alloc_context();
    

    
        // Note: for H.264 RTSP streams, the width and height are usually not specified (width and height are 0).  
    
        // These fields will become filled in once the first frame is decoded and the SPS is processed.
    
        codecCtx->width = width;
    
        codecCtx->height = height;
    

    
        codecCtx->extradata = av_malloc([privateData length]);
    
        codecCtx->extradata_size = [privateData length];
    
        [privateData getBytes:codecCtx->extradata length:codecCtx->extradata_size];
    
        codecCtx->pix_fmt = PIX_FMT_YUV420P;
    
#ifdef SHOW_DEBUG_MV
    
        codecCtx->debug_mv = 0xFF;
    
#endif
    

    
        srcFrame = avcodec_alloc_frame();
    
        dstFrame = avcodec_alloc_frame();
    

    
        int res = avcodec_open(codecCtx, codec);
    
        if (res < 0)
    
        {
    
            NSLog(@"Failed to initialize decoder");
    
        }
    
    }
    

    
    return self;    
    
}

    What is the privateData parameter of this function ? I don't know how to set the parameter...

    Now avcodec_decode_video2 returns -1 ;

    The framedata is coming successfully.

    How solve this problem.

    Thanks a lot.

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