id	summary	reporter	owner	description	type	status	priority	component	version	resolution	keywords	cc	blockedby	blocking	reproduced	analyzed
1913	Why file fails to open when saving frames from one file to other without any encoding/decoding?	theateist		"I started learning ffmpeg and for practice I use the following code to just save all frames from inFileName to outFileName. At first sight it success but the file fails to open with WindowsMediaPlayer. VLC Player opens it but I see strange colorful stripes at the bottom. In addition, the pix_fmt of inFileName is pal8 and of the outFileName is changed to bgr24, although I construct outFormatCtx the same as inFormatCtx.

What is the problem and why I get different pix_fmt in out file?

Thanks 


{{{
const char* inFileName = ""C:\\FlickAnimation.avi"";
	const char* outFileName = ""c:\\out.avi"";
	const char* outFileType = ""avi"";

	av_register_all();

	AVFormatContext* inFormatCtx = NULL;
	int err = avformat_open_input(&inFormatCtx, inFileName, NULL, NULL);
	if (err < 0) exit(1);

	err = av_find_stream_info(inFormatCtx);
	if (err < 0) exit(1);

	// Find video stream
	int videoStreamIndex = -1;
	for (unsigned int i = 0; i < inFormatCtx->nb_streams; ++i)
	{
		if (inFormatCtx->streams[i] && inFormatCtx->streams[i]->codec &&
				inFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO)
		{
			videoStreamIndex = i;
			break;
		}
	}
	if (videoStreamIndex == -1) exit(1);

	AVOutputFormat* outFormat = av_guess_format(outFileType, NULL, NULL);
	if (!outFormat) exit(1);

	AVFormatContext* outFormatCtx = NULL;
	err = avformat_alloc_output_context2(&outFormatCtx, outFormat, NULL, NULL);
	if (err < 0 || !outFormatCtx) exit(1);

	err = avio_open(&outFormatCtx->pb, outFileName, AVIO_FLAG_WRITE);
	if (err < 0) exit(1);

	// Create and initiate output stream
	AVStream* outStream = av_new_stream(outFormatCtx, 0);
	AVStream const* const inStream = inFormatCtx->streams[videoStreamIndex];
	AVCodec* codec = NULL;
	avcodec_get_context_defaults3(outStream->codec, inStream->codec->codec);
	
	outStream->codec->coder_type = AVMEDIA_TYPE_VIDEO;
	outStream->codec->sample_aspect_ratio = outStream->sample_aspect_ratio = inStream->sample_aspect_ratio;
	outStream->disposition = inStream->disposition;
	outStream->codec->bits_per_raw_sample = inStream->codec->bits_per_raw_sample;
	outStream->codec->chroma_sample_location = inStream->codec->chroma_sample_location;
	outStream->codec->codec_id = inStream->codec->codec_id;
	outStream->codec->codec_type = inStream->codec->codec_type;
	outStream->codec->bit_rate = inStream->codec->bit_rate;
	outStream->codec->rc_max_rate = inStream->codec->rc_max_rate;
	outStream->codec->rc_buffer_size = inStream->codec->rc_buffer_size;
	
	if (!outStream->codec->codec_tag)
    {		
        if (! outFormatCtx->oformat->codec_tag
            || av_codec_get_id (outFormatCtx->oformat->codec_tag, inStream->codec->codec_tag) == outStream->codec->codec_id
            || av_codec_get_tag(outFormatCtx->oformat->codec_tag, inStream->codec->codec_id) <= 0)
                    outStream->codec->codec_tag = inStream->codec->codec_tag;
    }

  	size_t extra_size_alloc = (inStream->codec->extradata_size > 0) ? (inStream->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE) : 0;
	if (extra_size_alloc)
	{
		outStream->codec->extradata = (uint8_t*)av_malloc(extra_size_alloc);
		memcpy(outStream->codec->extradata, inStream->codec->extradata, inStream->codec->extradata_size);
	}
	outStream->codec->extradata_size = inStream->codec->extradata_size;

	AVRational input_time_base = inStream->time_base;
	AVRational frameRate;
	frameRate.num = inStream->r_frame_rate.num;
	frameRate.den = inStream->r_frame_rate.den;
	
	outStream->r_frame_rate = frameRate;
	outStream->codec->time_base = inStream->codec->time_base;
	outStream->codec->pix_fmt = inStream->codec->pix_fmt;
	outStream->codec->width = inStream->codec->width;
	outStream->codec->height = inStream->codec->height;
	outStream->codec->has_b_frames = inStream->codec->has_b_frames;	
	if (!outStream->codec->sample_aspect_ratio.num)
	{
		AVRational r0 = {0, 1};
		outStream->codec->sample_aspect_ratio = outStream->sample_aspect_ratio = inStream->sample_aspect_ratio.num ? inStream->sample_aspect_ratio :
												inStream->codec->sample_aspect_ratio.num ? inStream->codec->sample_aspect_ratio : r0;
	}

	avformat_write_header(outFormatCtx, NULL);

	AVPacket packet;
	while(av_read_frame(inFormatCtx, &packet)>=0)
	{
		if (packet.stream_index == videoStreamIndex)
		{						
			err = av_interleaved_write_frame(outFormatCtx, &packet);
			if (err < 0) exit(1);
		}

		av_free_packet(&packet);
	}

	av_write_trailer(outFormatCtx);
	avio_close(outFormatCtx->pb);

	avformat_free_context(outFormatCtx);
	av_close_input_file(inFormatCtx);
}}}


d"	defect	closed	normal	undetermined	unspecified	invalid					0	0