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Revolution of Open-source and film making towards open film making
6 octobre 2011, par
Mis à jour : Juillet 2013
Langue : English
Type : Texte
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Sur d’autres sites (7359)
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Saving frames as JPG with FFMPEG (Visual Studio / C++)
10 novembre 2022, par Diego SatizabalI am trying to save all frames from a mp4 video in separate JPG files, I have a code that runs and actually saves something to JPG files but files are not recognized as images and nothing is showing.


Below my full code, I am using Visual Studio 2022 in Windows 11 and FFMPEG 5.1. The function that saves the images is save_frame_as_jpeg which is actually an adaption from the code provided here but changing the use of avcodec_encode_video2 for avcodec_send_frame/avcodec_receive_packet as indicated in the documentation.


I am obiously doing something wrong but cannot quite find it, BTW, I know that a simple command (ffmpeg -i input.mp4 -vf fps=1 vid_%d.png) will do this but I am requiring to do it by code.


Any help is appreciated, thanks in advance !


// FfmpegTests.cpp : This file contains the 'main' function. Program execution begins and ends there.
//
#pragma warning(disable : 4996)
extern "C"
{
 #include "libavformat/avformat.h"
 #include "libavcodec/avcodec.h"
 #include "libavfilter/avfilter.h"
 #include "libavutil/opt.h"
 #include "libavutil/avutil.h"
 #include "libavutil/error.h"
 #include "libavfilter/buffersrc.h"
 #include "libavfilter/buffersink.h"
 #include "libswscale/swscale.h"
}

#pragma comment(lib, "avcodec.lib")
#pragma comment(lib, "avformat.lib")
#pragma comment(lib, "avfilter.lib")
#pragma comment(lib, "avutil.lib")
#pragma comment(lib, "swscale.lib")

#include <cstdio>
#include <iostream>
#include <chrono>
#include <thread>


static AVFormatContext* fmt_ctx;
static AVCodecContext* dec_ctx;
AVFilterGraph* filter_graph;
AVFilterContext* buffersrc_ctx;
AVFilterContext* buffersink_ctx;
static int video_stream_index = -1;

const char* filter_descr = "scale=78:24,transpose=cclock";
static int64_t last_pts = AV_NOPTS_VALUE;

static int open_input_file(const char* filename)
{
 const AVCodec* dec;
 int ret;

 if ((ret = avformat_open_input(&fmt_ctx, filename, NULL, NULL)) < 0) {
 av_log(NULL, AV_LOG_ERROR, "Cannot open input file\n");
 return ret;
 }

 if ((ret = avformat_find_stream_info(fmt_ctx, NULL)) < 0) {
 av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n");
 return ret;
 }

 /* select the video stream */
 ret = av_find_best_stream(fmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &dec, 0);
 if (ret < 0) {
 av_log(NULL, AV_LOG_ERROR, "Cannot find a video stream in the input file\n");
 return ret;
 }
 video_stream_index = ret;

 /* create decoding context */
 dec_ctx = avcodec_alloc_context3(dec);
 if (!dec_ctx)
 return AVERROR(ENOMEM);
 avcodec_parameters_to_context(dec_ctx, fmt_ctx->streams[video_stream_index]->codecpar);

 /* init the video decoder */
 if ((ret = avcodec_open2(dec_ctx, dec, NULL)) < 0) {
 av_log(NULL, AV_LOG_ERROR, "Cannot open video decoder\n");
 return ret;
 }

 return 0;
}

static int init_filters(const char* filters_descr)
{
 char args[512];
 int ret = 0;
 const AVFilter* buffersrc = avfilter_get_by_name("buffer");
 const AVFilter* buffersink = avfilter_get_by_name("buffersink");
 AVFilterInOut* outputs = avfilter_inout_alloc();
 AVFilterInOut* inputs = avfilter_inout_alloc();
 AVRational time_base = fmt_ctx->streams[video_stream_index]->time_base;
 enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };

 filter_graph = avfilter_graph_alloc();
 if (!outputs || !inputs || !filter_graph) {
 ret = AVERROR(ENOMEM);
 goto end;
 }

 /* buffer video source: the decoded frames from the decoder will be inserted here. */
 snprintf(args, sizeof(args),
 "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
 dec_ctx->width, dec_ctx->height, dec_ctx->pix_fmt,
 time_base.num, time_base.den,
 dec_ctx->sample_aspect_ratio.num, dec_ctx->sample_aspect_ratio.den);

 ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in",
 args, NULL, filter_graph);
 if (ret < 0) {
 av_log(NULL, AV_LOG_ERROR, "Cannot create buffer source\n");
 goto end;
 }

 /* buffer video sink: to terminate the filter chain. */
 ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out",
 NULL, NULL, filter_graph);
 if (ret < 0) {
 av_log(NULL, AV_LOG_ERROR, "Cannot create buffer sink\n");
 goto end;
 }

 ret = av_opt_set_int_list(buffersink_ctx, "pix_fmts", pix_fmts, AV_PIX_FMT_NONE, AV_OPT_SEARCH_CHILDREN);
 if (ret < 0) {
 av_log(NULL, AV_LOG_ERROR, "Cannot set output pixel format\n");
 goto end;
 }

 outputs->name = av_strdup("in");
 outputs->filter_ctx = buffersrc_ctx;
 outputs->pad_idx = 0;
 outputs->next = NULL;

 inputs->name = av_strdup("out");
 inputs->filter_ctx = buffersink_ctx;
 inputs->pad_idx = 0;
 inputs->next = NULL;

 if ((ret = avfilter_graph_parse_ptr(filter_graph, filters_descr,
 &inputs, &outputs, NULL)) < 0)
 goto end;

 if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0)
 goto end;

end:
 avfilter_inout_free(&inputs);
 avfilter_inout_free(&outputs);

 return ret;
}

static void display_frame(const AVFrame* frame, AVRational time_base)
{
 int x, y;
 uint8_t* p0, * p;
 int64_t delay;

 if (frame->pts != AV_NOPTS_VALUE) {
 if (last_pts != AV_NOPTS_VALUE) {
 /* sleep roughly the right amount of time;
 * usleep is in microseconds, just like AV_TIME_BASE. */
 AVRational timeBaseQ;
 timeBaseQ.num = 1;
 timeBaseQ.den = AV_TIME_BASE;

 delay = av_rescale_q(frame->pts - last_pts, time_base, timeBaseQ);
 if (delay > 0 && delay < 1000000)
 std::this_thread::sleep_for(std::chrono::microseconds(delay));
 }
 last_pts = frame->pts;
 }

 /* Trivial ASCII grayscale display. */
 p0 = frame->data[0];
 puts("\033c");
 for (y = 0; y < frame->height; y++) {
 p = p0;
 for (x = 0; x < frame->width; x++)
 putchar(" .-+#"[*(p++) / 52]);
 putchar('\n');
 p0 += frame->linesize[0];
 }
 fflush(stdout);
}

int save_frame_as_jpeg(AVCodecContext* pCodecCtx, AVFrame* pFrame, int FrameNo) {
 int ret = 0;

 const AVCodec* jpegCodec = avcodec_find_encoder(AV_CODEC_ID_JPEG2000);
 if (!jpegCodec) {
 return -1;
 }
 AVCodecContext* jpegContext = avcodec_alloc_context3(jpegCodec);
 if (!jpegContext) {
 return -1;
 }

 jpegContext->pix_fmt = pCodecCtx->pix_fmt;
 jpegContext->height = pFrame->height;
 jpegContext->width = pFrame->width;
 jpegContext->time_base = AVRational{ 1,10 };

 ret = avcodec_open2(jpegContext, jpegCodec, NULL);
 if (ret < 0) {
 return ret;
 }
 FILE* JPEGFile;
 char JPEGFName[256];

 AVPacket packet;
 packet.data = NULL;
 packet.size = 0;
 av_init_packet(&packet);

 int gotFrame;

 ret = avcodec_send_frame(jpegContext, pFrame);
 if (ret < 0) {
 return ret;
 }

 ret = avcodec_receive_packet(jpegContext, &packet);
 if (ret < 0) {
 return ret;
 }

 sprintf(JPEGFName, "c:\\folder\\dvr-%06d.jpg", FrameNo);
 JPEGFile = fopen(JPEGFName, "wb");
 fwrite(packet.data, 1, packet.size, JPEGFile);
 fclose(JPEGFile);

 av_packet_unref(&packet);
 avcodec_close(jpegContext);
 return 0;
}

int main(int argc, char** argv)
{
 AVFrame* frame;
 AVFrame* filt_frame;
 AVPacket* packet;
 int ret;

 if (argc != 2) {
 fprintf(stderr, "Usage: %s file\n", argv[0]);
 exit(1);
 }

 frame = av_frame_alloc();
 filt_frame = av_frame_alloc();
 packet = av_packet_alloc();

 if (!frame || !filt_frame || !packet) {
 fprintf(stderr, "Could not allocate frame or packet\n");
 exit(1);
 }

 if ((ret = open_input_file(argv[1])) < 0)
 goto end;
 if ((ret = init_filters(filter_descr)) < 0)
 goto end;

 while (true)
 {
 if ((ret = av_read_frame(fmt_ctx, packet)) < 0)
 break;

 if (packet->stream_index == video_stream_index) {
 ret = avcodec_send_packet(dec_ctx, packet);
 if (ret < 0) {
 av_log(NULL, AV_LOG_ERROR, "Error while sending a packet to the decoder\n");
 break;
 }

 while (ret >= 0)
 {
 ret = avcodec_receive_frame(dec_ctx, frame);
 if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
 break;
 }
 else if (ret < 0) {
 av_log(NULL, AV_LOG_ERROR, "Error while receiving a frame from the decoder\n");
 goto end;
 }

 frame->pts = frame->best_effort_timestamp;

 /* push the decoded frame into the filtergraph */
 if (av_buffersrc_add_frame_flags(buffersrc_ctx, frame, AV_BUFFERSRC_FLAG_KEEP_REF) < 0) {
 av_log(NULL, AV_LOG_ERROR, "Error while feeding the filtergraph\n");
 break;
 }

 /* pull filtered frames from the filtergraph */
 while (1) {
 ret = av_buffersink_get_frame(buffersink_ctx, filt_frame);
 if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
 break;
 if (ret < 0)
 goto end;
 display_frame(filt_frame, buffersink_ctx->inputs[0]->time_base);
 av_frame_unref(filt_frame);
 
 ret = save_frame_as_jpeg(dec_ctx, frame, dec_ctx->frame_number);
 if (ret < 0)
 goto end;
 }
 av_frame_unref(frame);
 }
 }
 av_packet_unref(packet);
 }

end:
 avfilter_graph_free(&filter_graph);
 avcodec_free_context(&dec_ctx);
 avformat_close_input(&fmt_ctx);
 av_frame_free(&frame);
 av_frame_free(&filt_frame);
 av_packet_free(&packet);

 if (ret < 0 && ret != AVERROR_EOF) {
 char errBuf[AV_ERROR_MAX_STRING_SIZE]{0};
 int res = av_strerror(ret, errBuf, AV_ERROR_MAX_STRING_SIZE);
 fprintf(stderr, "Error: %s\n", errBuf);
 exit(1);
 }

 exit(0);
}
</thread></chrono></iostream></cstdio>

-
FFMPEG No such filter : 'format=nv12|vaapi,hwupload'
14 novembre 2022, par Devin DixonI'm on a AWS g4ad instance and I am trying to get hardware accelleration with the GPU to work. with ffmpeg. A base line test is this :


ffmpeg -y -vaapi_device /dev/dri/renderD128 -v info -thread_queue_size 10000 -i video.mp4 -c:v h264_vaapi -vf 'format=nv12|vaapi,hwupload' -crf 25 -tune zerolatency -g 120 -r 60 -pix_fmt yuv420p -preset faster -maxrate 14000k -bufsize 14000k -strict -2 -ar 44100 -b:a 128k -af aresample=async=1 -acodec aac file_out.mp4


The above works, GPU is installed and working correctly. In my actual use case, I am grabbing the screen from an X11Grab, which works without the GPU and normal libx264 but fails when I add try to use h264_vaapi. The command I use is below :


/usr/bin/ffmpeg -vaapi_device /dev/dri/renderD128 -y -v info -f x11grab -draw_mouse 0 -r 60 -s 1920x1080 -thread_queue_size 10000 -i :0.0+0,0 -f alsa -thread_queue_size 10000 -i plug:bsnoop -acodec aac -strict -2 -ar 44100 -b:a 128k -af aresample=async=1 -c:v h264_vaapi -vf 'format=nv12|vaapi,hwupload' -preset faster -maxrate 14000k -bufsize 14000k -pix_fmt yuv420p -r 60 -crf 25 -g 120 -tune zerolatency -f flv rtmp://[to_an_rtmp source]

And my output is this:

2022-11-14 02:08:30.928 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: ffmpeg version 5.1.2-0ubuntu1~18.04.sav1.1 Copyright (c) 2000-2022 the FFmpeg developers
2022-11-14 02:08:30.928 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: built with gcc 7 (Ubuntu 7.5.0-6ubuntu2~18.04.sav0)
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: configuration: --prefix=/usr --extra-version='0ubuntu1~18.04.sav1.1' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-gnutls --enable-ladspa --enable-lcms2 --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libjxl --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librist --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-sndio --enable-pocketsphinx --enable-librsvg --enable-crystalhd --enable-libmfx --enable-libsvtav1 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-libplacebo --enable-librav1e --enable-shared
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libavutil 57. 28.100 / 57. 28.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libavcodec 59. 37.100 / 59. 37.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libavformat 59. 27.100 / 59. 27.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libavdevice 59. 7.100 / 59. 7.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libavfilter 8. 44.100 / 8. 44.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libswscale 6. 7.100 / 6. 7.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libswresample 4. 7.100 / 4. 7.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: libpostproc 56. 6.100 / 56. 6.100
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: [x11grab @ 0x56155ee70ac0] Stream #0: not enough frames to estimate rate; consider increasing probesize
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Input #0, x11grab, from ':0.0+0,0':
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Duration: N/A, start: 1668391710.975066, bitrate: 3981312 kb/s
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Stream #0:0: Video: rawvideo (BGR[0] / 0x524742), bgr0, 1920x1080, 3981312 kb/s, 60 fps, 1000k tbr, 1000k tbn
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Guessed Channel Layout for Input Stream #1.0 : stereo
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Input #1, alsa, from 'plug:bsnoop':
2022-11-14 02:08:31.105 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Duration: N/A, start: 1668391710.731953, bitrate: 1536 kb/s
2022-11-14 02:08:31.106 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Stream #1:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
2022-11-14 02:08:31.106 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Codec AVOption crf (Select the quality for constant quality mode) specified for output file #0 (rtmp://ingest.bingewave.com/live/ce98c9bb-78b0-4ee5-8a8e-af35160da695-broadcast?sign=1668996507-c340acfb5219383f660d41057a050de6) has not been used for any stream. The most likely reason is either wrong type (e.g. a video option with no video streams) or that it is a private option of some encoder which was not actually used for any stream.
2022-11-14 02:08:31.106 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Codec AVOption preset (Encoding preset) specified for output file #0 (rtmp://ingest.bingewave.com/live/ce98c9bb-78b0-4ee5-8a8e-af35160da695-broadcast?sign=1668996507-c340acfb5219383f660d41057a050de6) has not been used for any stream. The most likely reason is either wrong type (e.g. a video option with no video streams) or that it is a private option of some encoder which was not actually used for any stream.
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Codec AVOption tune (The metric that the encoder tunes for. Automatically chosen by the encoder by default) specified for output file #0 (rtmp://ingest.bingewave.com/live/ce98c9bb-78b0-4ee5-8a8e-af35160da695-broadcast?sign=1668996507-c340acfb5219383f660d41057a050de6) has not been used for any stream. The most likely reason is either wrong type (e.g. a video option with no video streams) or that it is a private option of some encoder which was not actually used for any stream.
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Stream mapping:
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (h264_vaapi))
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Stream #1:0 -> #0:1 (pcm_s16le (native) -> aac (native))
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Press [q] to stop, [?] for help
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: [AVFilterGraph @ 0x56155ee5d880] No such filter: 'format=nv12|vaapi,hwupload'
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Error reinitializing filters!
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Failed to inject frame into filter network: Invalid argument
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Error while processing the decoded data for stream #0:0
2022-11-14 02:08:31.237 INFO: [557] LoggingUtils$Companion$OutputLogger$1.invoke$lambda-0#42: Conversion failed!
root@ip-172-31-90-180:~# 


I see that is failing because No such filter : 'format=nv12|vaapi,hwupload', which I don't get when I run the other command. What am I doing wrong here ?


-
How to send libmmpeg AVPacket through WebRTC (using libdatachannel)
29 mars 2022, par mikeI'm encoding a video frame with the
ffmpeglibraries, generating anAVPacketwith compressed data.

Thanks to some recent advice here on S/O, I am trying to send that frame over a network using the
WebRTClibrarylibdatachannel, specifically by adapting the example here :

https://github.com/paullouisageneau/libdatachannel/tree/master/examples/streamer

I am seeing problems inside
h264rtppacketizer.cpp(part of the library, not the example) which are almost certainly to do with how I'm providing the sample data.
(I don't think that this is anything to do with libdatachannel specifically, it will be an issue with what I'm sending)

The example code reads each encoded frame from a file, and populates a
sampleby setting the content of the file to the contents of the file :

sample = *reinterpret_cast *>(&fileContents);

sampleis just astd::vector<byte>;</byte>

I have naively copied the contents of an
AVPacket->datapointer into thesamplevector :

sample.resize(pkt->size);
memcpy(sample.data(), pkt->data, pkt->size * sizeof(std::byte)); 


but the packetizer is falling over when trying to get length values out of that data.
Specifically, in the following code, the first iteration gets a length of 1, but the second, looking up index 5, gives 1119887324. This is way too big for my data, which is only 3526 bytes (the whole frame is a single colour so likely to be small once encoded) :


while (index < message->size()) {
assert(index + 4 < message->size());
auto lengthPtr = (uint32_t *)(message->data() + index);
uint32_t length = ntohl(*lengthPtr);
auto naluStartIndex = index + 4;
auto naluEndIndex = naluStartIndex + length;
assert(naluEndIndex <= message->size()); 
 
auto begin = message->begin() + naluStartIndex;
auto end = message->begin() + naluEndIndex;
nalus->push_back(std::make_shared<nalunit>(begin, end));
index = naluEndIndex;
}
</nalunit>

Here is a dump of


uint32_t length = ntohl(*lengthPtr);


for the first few elements of the message (
*lengthPtrin parentheses) :

[2022-03-29 15:12:01.182] [info] index 0: 1 (16777216)
[2022-03-29 15:12:01.183] [info] index 1: 359 (1728118784)
[2022-03-29 15:12:01.184] [info] index 2: 91970 (1114046720)
[2022-03-29 15:12:01.186] [info] index 3: 23544512 (3225577217)
[2022-03-29 15:12:01.186] [info] index 4: 1732427807 (532693607)
[2022-03-29 15:12:01.187] [info] index 5: 1119887324 (3693068354)
[2022-03-29 15:12:01.188] [info] index 6: 3223313413 (98312128)
[2022-03-29 15:12:01.188] [info] index 7: 534512896 (384031)
[2022-03-29 15:12:01.188] [info] index 8: 3691315291 (1526728156)
[2022-03-29 15:12:01.189] [info] index 9: 83909537 (2707095557)
[2022-03-29 15:12:01.189] [info] index 10: 6004992 (10574592)
[2022-03-29 15:12:01.190] [info] index 11: 1537277952 (41307)
[2022-03-29 15:12:01.190] [info] index 12: 2701131779 (50331809)
[2022-03-29 15:12:01.192] [info] index 13: 768 (196608)


(I know I should post a complete sample, I am working on it)


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I am fairly sure I am just missing something basic. E.g. am I supposed to do something with the
AVPacketside_data, does AVPacket have or miss some header info ?

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If I just fwrite the
pkt->datafor a single frame to disk, I can read the codec information with ffprobe :







Input #0, h264, from 'encodedOut.h264':
Duration: N/A, bitrate: N/A
Stream #0:0: Video: h264 (Constrained Baseline), yuv420p(progressive), 1280x720, 30 tbr, 1200k tbn


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- whereas the same for the example input files (again a single frame) gives the following :




[h264 @ 000001c88d1135c0] Format h264 detected only with low score of 1, misdetection possible!
[h264 @ 000001c88f337400] missing picture in access unit with size 85306
[extract_extradata @ 000001c88d11ee40] No start code is found.
sample-0.h264: Invalid data found when processing input


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