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The pirate bay depuis la Belgique
1er avril 2013, par
Mis à jour : Avril 2013
Langue : français
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HTML5 audio and video support
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Sur d’autres sites (6859)
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Android h264 decode non-existing PPS 0 referenced
22 janvier 2014, par nmxprimeIn 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 0Edit : Changing GOP value :
If i change
c->gop_size = 3;
as expected it emitsone I frame
every three frames. Thenon-existing PPS 0 referenced
message is not there for in every third execution, but all other have this message -
Error in video streaming using libavformat : VBV buffer size not set, muxing may fail
15 janvier 2014, par Blue SkyI 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 ?
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ffmpeg mysteriously adding start delay [migrated]
13 janvier 2014, par swizzcheezWhen converting a mp4 to TS, I am observing ffmpeg adding a "start" delay that the input file did not seem to possess. For my input, ffprobe reveals :
ffprobe version N-57943-g7b76976 Copyright (c) 2007-2013 the FFmpeg developers
built on Nov 6 2013 14:00:40 with gcc 4.4.5 (Debian 4.4.5-8)
configuration: --enable-libx264 --enable-gpl
libavutil 52. 52.100 / 52. 52.100
libavcodec 55. 41.100 / 55. 41.100
libavformat 55. 21.100 / 55. 21.100
libavdevice 55. 5.100 / 55. 5.100
libavfilter 3. 90.102 / 3. 90.102
libswscale 2. 5.101 / 2. 5.101
libswresample 0. 17.104 / 0. 17.104
libpostproc 52. 3.100 / 52. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'output.mp4-in-7A8FEADA-5EA6-11E3-AD13-4DD2258FBC88.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: mp42mp41
creation_time : 2013-11-08 15:15:12
Duration: 00:00:11.56, start: 0.000000, bitrate: 2994 kb/s
Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv), 1280x720 [SAR 1:1 DAR 16:9], 2807 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
Metadata:
creation_time : 2013-11-08 15:15:12
handler_name : ?Mainconcept Video Media Handler
Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 189 kb/s (default)
Metadata:
creation_time : 2013-11-08 15:15:12
handler_name : #Mainconcept MP4 Sound Media HandlerBut when processed using ffmpeg :
ffmpeg -i '/tmp/test-no-qp.C2162DFC-6297-11E3-A68D-05E505A3FB93/output.mp4-in-7A8FEADA-5EA6-11E3-AD13-4DD2258FBC88.mp4' -s 1920x1080 -preset ultrafast -f mpegts -c:v libx264 -qp:v 18 `enter code here`
I get an extra start delay :
(Snipping the same headers from the input side)
Input #0, mpegts, from 'output.mp4-out-7A8FEADA-5EA6-11E3-AD13-4DD2258FBC88.mp4':
Duration: 00:00:11.55, start: 1.400000, bitrate: 1985 kb/s
Program 1
Metadata:
service_name : Service01
service_provider: FFmpeg
Stream #0:0[0x100]: Video: h264 (Constrained Baseline) ([27][0][0][0] / 0x001B), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
Stream #0:1[0x101](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 128 kb/sDuration seems to have been adjusted as well, but I didn't ask for the adjustment. How do I get rid of that ? What did I do that triggered that effect ? Is there something else about my ffmpeg line that looks off ?
(ffmpeg version is the same as the ffprobe above.)