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  • Error in video streaming using libavformat : VBV buffer size not set, muxing may fail

    15 janvier 2014, par Blue Sky

    I stream a video using libavformat as follows :

    static AVStream *add_stream(AVFormatContext *oc, AVCodec **codec,
    
                        enum AVCodecID codec_id)
    
{
    
AVCodecContext *c;
    
AVStream *st;
    
/* find the encoder */
    
*codec = avcodec_find_encoder(codec_id);
    
if (!(*codec)) {
    
    fprintf(stderr, "Could not find encoder for '%s'\n",
    
            avcodec_get_name(codec_id));
    
    exit(1);
    
}
    
st = avformat_new_stream(oc, *codec);
    
if (!st) {
    
    fprintf(stderr, "Could not allocate stream\n");
    
    exit(1);
    
}
    
st->id = oc->nb_streams-1;
    
c = st->codec;
    
switch ((*codec)->type) {
    
case AVMEDIA_TYPE_AUDIO:
    
    c->sample_fmt  = (*codec)->sample_fmts ?
    
        (*codec)->sample_fmts[0] : AV_SAMPLE_FMT_FLTP;
    
    c->bit_rate    = 64000;
    
    c->sample_rate = 44100;
    
    c->channels    = 2;
    
    break;
    
case AVMEDIA_TYPE_VIDEO:
    
    c->codec_id = codec_id;
    
    c->bit_rate = 400000;
    
    /* Resolution must be a multiple of two. */
    
    c->width    = outframe_width;
    
    c->height   = outframe_height;
    
    /* timebase: This is the fundamental unit of time (in seconds) in terms
    
     * of which frame timestamps are represented. For fixed-fps content,
    
     * timebase should be 1/framerate and timestamp increments should be
    
     * identical to 1. */
    
    c->time_base.den = STREAM_FRAME_RATE;
    
    c->time_base.num = 1;
    
    c->gop_size      = 12; /* emit one intra frame every twelve frames at most */
    
    c->pix_fmt       = STREAM_PIX_FMT;
    
    if (c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
    
        /* just for testing, we also add B frames */
    
        c->max_b_frames = 2;
    
    }
    
    if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
    
        /* Needed to avoid using macroblocks in which some coeffs overflow.
    
         * This does not happen with normal video, it just happens here as
    
         * the motion of the chroma plane does not match the luma plane. */
    
        c->mb_decision = 2;
    
    }
    
break;
    
default:
    
    break;
    
}
    
/* Some formats want stream headers to be separate. */
    
if (oc->oformat->flags & AVFMT_GLOBALHEADER)
    
    c->flags |= CODEC_FLAG_GLOBAL_HEADER;
    
return st;
    
}

    But when I run this code, I get the following error/warning :

    [mpeg @ 01f3f040] VBV buffer size not set, muxing may fail

    Do you know how I can set the VBV buffer size in the code ? In fact, when I use ffplay to display the streamed video, ffplay doesn't show anything for short videos but for long videos, it start displaying the video immediately. So, it looks like ffplay needs a buffer to be filled up by some amount so that it can start displaying the stream. Am I right ?

  • Android h264 decode non-existing PPS 0 referenced

    22 janvier 2014, par nmxprime

    In Android JNI, using ffmpeg with libx264 use below codes to encode and decode raw rgb data !. I should use swscale to convert rgb565 to yuv420p as required by H.264. But not clear about this conversion.Please help, where i am wrong, with regard the log i get !

    Code for Encoding

    codecinit()- called once(JNI wrapper function)

    int Java_com_my_package_codecinit (JNIEnv *env, jobject thiz) {
    
avcodec_register_all();
    
codec = avcodec_find_encoder(AV_CODEC_ID_H264);//AV_CODEC_ID_MPEG1VIDEO);
    
if(codec->id == AV_CODEC_ID_H264)
    
    __android_log_write(ANDROID_LOG_ERROR, "set","h264_encoder");
    

    
if (!codec) {
    
    fprintf(stderr, "codec not found\n");
    
    __android_log_write(ANDROID_LOG_ERROR, "codec", "not found");
    

    
}
    
    __android_log_write(ANDROID_LOG_ERROR, "codec", "alloc-contest3");
    
c= avcodec_alloc_context3(codec);
    
if(c == NULL)
    
    __android_log_write(ANDROID_LOG_ERROR, "avcodec","context-null");
    

    
picture= av_frame_alloc();
    

    
if(picture == NULL)
    
    __android_log_write(ANDROID_LOG_ERROR, "picture","context-null");
    

    
c->bit_rate = 400000;
    
c->height = 800;
    
c->time_base= (AVRational){1,25};
    
c->gop_size = 10; 
    
c->max_b_frames=1;
    
c->pix_fmt = AV_PIX_FMT_YUV420P;
    
outbuf_size = 768000;
    
c->width = 480;
    

    
size = (c->width * c->height);
    

    
if (avcodec_open2(c, codec,NULL) < 0) {
    

    
__android_log_write(ANDROID_LOG_ERROR, "codec", "could not open");
    

    

    
}
    

    
ret = av_image_alloc(picture->data, picture->linesize, c->width, c->height,
    
                     c->pix_fmt, 32);
    
if (ret < 0) {
    
        __android_log_write(ANDROID_LOG_ERROR, "image","alloc-failed");
    
    fprintf(stderr, "could not alloc raw picture buffer\n");
    

    
}
    

    
picture->format = c->pix_fmt;
    
picture->width  = c->width;
    
picture->height = c->height;
    
return 0;
    

    
}

    encodeframe()-called in a while loop

    int Java_com_my_package_encodeframe (JNIEnv *env, jobject thiz,jbyteArray buffer) {
    
jbyte *temp= (*env)->GetByteArrayElements(env, buffer, 0);
    
Output = (char *)temp;
    
const uint8_t * const inData[1] = { Output }; 
    
const int inLinesize[1] = { 2*c->width };
    

    
//swscale should implement here
    

    
    av_init_packet(&pkt);
    
    pkt.data = NULL;    // packet data will be allocated by the encoder
    
    pkt.size = 0;
    

    
    fflush(stdout);
    
picture->data[0] = Output;
    
ret = avcodec_encode_video2(c, &pkt, picture,&got_output);
    

    
    fprintf(stderr,"ret = %d, got-out = %d \n",ret,got_output);
    
     if (ret < 0) {
    
                __android_log_write(ANDROID_LOG_ERROR, "error","encoding");
    
        if(got_output > 0)
    
        __android_log_write(ANDROID_LOG_ERROR, "got_output","is non-zero");
    

    
    }
    

    
    if (got_output) {
    
        fprintf(stderr,"encoding frame %3d (size=%5d): (ret=%d)\n", 1, pkt.size,ret);
    
        fprintf(stderr,"before caling decode");
    
        decode_inline(&pkt); //function that decodes right after the encode
    
        fprintf(stderr,"after caling decode");
    

    

    
        av_free_packet(&pkt);
    
    }
    

    

    
fprintf(stderr,"y val: %d \n",y);
    

    

    
(*env)->ReleaseByteArrayElements(env, buffer, Output, 0);
    
return ((ret));
    
}

    decode_inline() function

    decode_inline(AVPacket *avpkt){
    
AVCodec *codec;
    
AVCodecContext *c = NULL;
    
int frame, got_picture, len = -1,temp=0;
    

    
AVFrame *rawFrame, *rgbFrame;
    
uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE];
    
char buf[1024];
    
char rawBuf[768000],rgbBuf[768000];
    

    
struct SwsContext *sws_ctx;
    

    
memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE);
    
avcodec_register_all();
    

    
c= avcodec_alloc_context3(codec);
    
if(c == NULL)
    
    __android_log_write(ANDROID_LOG_ERROR, "avcodec","context-null");
    

    
codec = avcodec_find_decoder(AV_CODEC_ID_H264);
    
if (!codec) {
    
    fprintf(stderr, "codec not found\n");
    
    fprintf(stderr, "codec = %p \n", codec);
    
    }
    
c->pix_fmt = AV_PIX_FMT_YUV420P;
    
c->width = 480;
    
c->height = 800;
    

    
rawFrame = av_frame_alloc();
    
rgbFrame = av_frame_alloc();
    

    
if (avcodec_open2(c, codec, NULL) < 0) {
    
    fprintf(stderr, "could not open codec\n");
    
    exit(1);
    
    }
    
sws_ctx = sws_getContext(c->width, c->height,/*PIX_FMT_RGB565BE*/
    
            PIX_FMT_YUV420P, c->width, c->height, AV_PIX_FMT_RGB565/*PIX_FMT_YUV420P*/,
    
            SWS_BILINEAR, NULL, NULL, NULL);
    

    

    
frame = 0;
    

    
unsigned short *decodedpixels = &rawBuf;
    
rawFrame->data[0] = &rawBuf;
    
rgbFrame->data[0] = &rgbBuf;
    

    
fprintf(stderr,"size of avpkt %d \n",avpkt->size);
    
temp = avpkt->size;
    
while (temp > 0) {
    
        len = avcodec_decode_video2(c, rawFrame, &got_picture, avpkt);
    

    
        if (len < 0) {
    
            fprintf(stderr, "Error while decoding frame %d\n", frame);
    
            exit(1);
    
            }
    
        temp -= len;
    
        avpkt->data += len;
    

    
        if (got_picture) {
    
            printf("saving frame %3d\n", frame);
    
            fflush(stdout);
    
        //TODO  
    
        //memcpy(decodedpixels,rawFrame->data[0],rawFrame->linesize[0]); 
    
        //  decodedpixels +=rawFrame->linesize[0];
    

    
            frame++;
    
            }
    

    
        }
    

    
avcodec_close(c);
    
av_free(c);
    
//free(rawBuf);
    
//free(rgbBuf);
    
av_frame_free(&rawFrame);
    
av_frame_free(&rgbFrame);

    }

    The log i get

    For the decode_inline() function :

    01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] Invalid mix of idr and non-idr slices
    
01-02 14:50:50.160: I/stderr(3407): Error while decoding frame 0

    Edit : Changing GOP value :

    If i change c->gop_size = 3; as expected it emits one I frame every three frames. The non-existing PPS 0 referenced message is not there for in every third execution, but all other have this message

  • Android h264 decode non-existing PPS 0 referenced

    22 janvier 2014, par nmxprime

    In Android JNI, using ffmpeg with libx264 use below codes to encode and decode raw rgb data !. I should use swscale to convert rgb565 to yuv420p as required by H.264. But not clear about this conversion.Please help, where i am wrong, with regard the log i get !

    Code for Encoding

    codecinit()- called once(JNI wrapper function)

    int Java_com_my_package_codecinit (JNIEnv *env, jobject thiz) {
    
avcodec_register_all();
    
codec = avcodec_find_encoder(AV_CODEC_ID_H264);//AV_CODEC_ID_MPEG1VIDEO);
    
if(codec->id == AV_CODEC_ID_H264)
    
    __android_log_write(ANDROID_LOG_ERROR, "set","h264_encoder");
    

    
if (!codec) {
    
    fprintf(stderr, "codec not found\n");
    
    __android_log_write(ANDROID_LOG_ERROR, "codec", "not found");
    

    
}
    
    __android_log_write(ANDROID_LOG_ERROR, "codec", "alloc-contest3");
    
c= avcodec_alloc_context3(codec);
    
if(c == NULL)
    
    __android_log_write(ANDROID_LOG_ERROR, "avcodec","context-null");
    

    
picture= av_frame_alloc();
    

    
if(picture == NULL)
    
    __android_log_write(ANDROID_LOG_ERROR, "picture","context-null");
    

    
c->bit_rate = 400000;
    
c->height = 800;
    
c->time_base= (AVRational){1,25};
    
c->gop_size = 10; 
    
c->max_b_frames=1;
    
c->pix_fmt = AV_PIX_FMT_YUV420P;
    
outbuf_size = 768000;
    
c->width = 480;
    

    
size = (c->width * c->height);
    

    
if (avcodec_open2(c, codec,NULL) < 0) {
    

    
__android_log_write(ANDROID_LOG_ERROR, "codec", "could not open");
    

    

    
}
    

    
ret = av_image_alloc(picture->data, picture->linesize, c->width, c->height,
    
                     c->pix_fmt, 32);
    
if (ret < 0) {
    
        __android_log_write(ANDROID_LOG_ERROR, "image","alloc-failed");
    
    fprintf(stderr, "could not alloc raw picture buffer\n");
    

    
}
    

    
picture->format = c->pix_fmt;
    
picture->width  = c->width;
    
picture->height = c->height;
    
return 0;
    

    
}

    encodeframe()-called in a while loop

    int Java_com_my_package_encodeframe (JNIEnv *env, jobject thiz,jbyteArray buffer) {
    
jbyte *temp= (*env)->GetByteArrayElements(env, buffer, 0);
    
Output = (char *)temp;
    
const uint8_t * const inData[1] = { Output }; 
    
const int inLinesize[1] = { 2*c->width };
    

    
//swscale should implement here
    

    
    av_init_packet(&pkt);
    
    pkt.data = NULL;    // packet data will be allocated by the encoder
    
    pkt.size = 0;
    

    
    fflush(stdout);
    
picture->data[0] = Output;
    
ret = avcodec_encode_video2(c, &pkt, picture,&got_output);
    

    
    fprintf(stderr,"ret = %d, got-out = %d \n",ret,got_output);
    
     if (ret < 0) {
    
                __android_log_write(ANDROID_LOG_ERROR, "error","encoding");
    
        if(got_output > 0)
    
        __android_log_write(ANDROID_LOG_ERROR, "got_output","is non-zero");
    

    
    }
    

    
    if (got_output) {
    
        fprintf(stderr,"encoding frame %3d (size=%5d): (ret=%d)\n", 1, pkt.size,ret);
    
        fprintf(stderr,"before caling decode");
    
        decode_inline(&pkt); //function that decodes right after the encode
    
        fprintf(stderr,"after caling decode");
    

    

    
        av_free_packet(&pkt);
    
    }
    

    

    
fprintf(stderr,"y val: %d \n",y);
    

    

    
(*env)->ReleaseByteArrayElements(env, buffer, Output, 0);
    
return ((ret));
    
}

    decode_inline() function

    decode_inline(AVPacket *avpkt){
    
AVCodec *codec;
    
AVCodecContext *c = NULL;
    
int frame, got_picture, len = -1,temp=0;
    

    
AVFrame *rawFrame, *rgbFrame;
    
uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE];
    
char buf[1024];
    
char rawBuf[768000],rgbBuf[768000];
    

    
struct SwsContext *sws_ctx;
    

    
memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE);
    
avcodec_register_all();
    

    
c= avcodec_alloc_context3(codec);
    
if(c == NULL)
    
    __android_log_write(ANDROID_LOG_ERROR, "avcodec","context-null");
    

    
codec = avcodec_find_decoder(AV_CODEC_ID_H264);
    
if (!codec) {
    
    fprintf(stderr, "codec not found\n");
    
    fprintf(stderr, "codec = %p \n", codec);
    
    }
    
c->pix_fmt = AV_PIX_FMT_YUV420P;
    
c->width = 480;
    
c->height = 800;
    

    
rawFrame = av_frame_alloc();
    
rgbFrame = av_frame_alloc();
    

    
if (avcodec_open2(c, codec, NULL) < 0) {
    
    fprintf(stderr, "could not open codec\n");
    
    exit(1);
    
    }
    
sws_ctx = sws_getContext(c->width, c->height,/*PIX_FMT_RGB565BE*/
    
            PIX_FMT_YUV420P, c->width, c->height, AV_PIX_FMT_RGB565/*PIX_FMT_YUV420P*/,
    
            SWS_BILINEAR, NULL, NULL, NULL);
    

    

    
frame = 0;
    

    
unsigned short *decodedpixels = &rawBuf;
    
rawFrame->data[0] = &rawBuf;
    
rgbFrame->data[0] = &rgbBuf;
    

    
fprintf(stderr,"size of avpkt %d \n",avpkt->size);
    
temp = avpkt->size;
    
while (temp > 0) {
    
        len = avcodec_decode_video2(c, rawFrame, &got_picture, avpkt);
    

    
        if (len < 0) {
    
            fprintf(stderr, "Error while decoding frame %d\n", frame);
    
            exit(1);
    
            }
    
        temp -= len;
    
        avpkt->data += len;
    

    
        if (got_picture) {
    
            printf("saving frame %3d\n", frame);
    
            fflush(stdout);
    
        //TODO  
    
        //memcpy(decodedpixels,rawFrame->data[0],rawFrame->linesize[0]); 
    
        //  decodedpixels +=rawFrame->linesize[0];
    

    
            frame++;
    
            }
    

    
        }
    

    
avcodec_close(c);
    
av_free(c);
    
//free(rawBuf);
    
//free(rgbBuf);
    
av_frame_free(&rawFrame);
    
av_frame_free(&rgbFrame);

    }

    The log i get

    For the decode_inline() function :

    01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] non-existing PPS 0 referenced
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] decode_slice_header error
    
01-02 14:50:50.160: I/stderr(3407): [h264 @ 0x8db540] Invalid mix of idr and non-idr slices
    
01-02 14:50:50.160: I/stderr(3407): Error while decoding frame 0

    Edit : Changing GOP value :

    If i change c->gop_size = 3; as expected it emits one I frame every three frames. The non-existing PPS 0 referenced message is not there for in every third execution, but all other have this message

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