[Libav-user] AVPacket av_malloc av_packet_unref question
I have a piece of code that appears to work, that is to say it does stream
packets..
It goes like this:
av_packet = (AVPacket *) av_malloc( sizeof( AVPacket ) );
while ( 1 ) /// reading in from file out to mpegts
{
av_read_frame( av_in_fmt_ctx, m_avpacket );
[...]
ret = av_interleaved_write_frame( av_out_fmt_ctx, av_packet );
av_packet_unref( av_packet );
}
In the include headers I find this type of verbage ::
* The side data is always allocated with av_malloc(), copied by
* av_packet_ref() and freed by av_packet_unref().
From reading the av_read_frame I know the packed is a reference to another
packet (at least the buf).
Question :
What is av_malloc doing if the packet is getting unref and passed back into
av_read_frame without another malloc?
Follow Up :
Is this thread safe?
Thanks
cco
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Re: [Libav-user] imgutils.h decode dst buffer going from avpicture_fill to av_image_fill_arrays
On 08/19/2016 04:54 AM, ssshukla26 wrote: For example let suppose "decoder->dst_data[0]" has YUV buffer and its alignment is 1. --- //Allocate AVFrame data and linesize av_image_alloc(avframe->data, avframe->linesize, decoder->video_resolution.frame_width, decoder->video_resolution.frame_height, AV_PIX_FMT_YUV420P, 1); Below are the 3 methods to fill data array of avframe. --- //1) if your Y, U, V buffers are contiguous and have the correct size, This is deprecated avpicture_fill((AVPicture*) avframe, decoder->dst_data[0], avframe->format, avframe->width, avframe->height); --- //2) if your Y, U, V buffers are non-contiguous, This is deprecated // Initialize avframe->linesize avpicture_fill((AVPicture*) avframe, NULL, avframe->format, avframe->width, avframe->height); //Set avframe->data pointers manually avframe->data[0] = decoder->dst_data[0];//Y-Buffer avframe->data[1] = decoder->dst_data[1];//U-Buffer avframe->data[2] = decoder->dst_data[2];//V-Buffer --- //3) Fill data array of avframe, as decoder->dst_data[0] alignment is 1 use the same alignment. av_image_fill_arrays(avframe->data, avframe->linesize, decoder->dst_data[0], avframe->format, avframe->width, avframe->height, *1*); Good explanation. I figured out #3 yesterday and avoided the deprecated call m_out_bufers[ m_buf_idx ] = (uint8_t*) av_malloc( av_image_get_buffer_size( AV_PIX_FMT_RGB24, m_avcodec_ctx->width, m_avcodec_ctx->height, 1 ) ); if ( !m_out_bufers[ m_buf_idx ] )[...] av_image_fill_arrays( m_avframeRGB[ m_buf_idx ]->data, m_avframeRGB[ m_buf_idx ]->linesize, m_out_bufers[ m_buf_idx ], AV_PIX_FMT_RGB24, m_avcodec_ctx->width, m_avcodec_ctx->height, 1 ); Can I replace the av_malloc for out_buffers with an input pointer? size_t required_size = av_image_get_buffer_size( AV_PIX_FMT_RGB24, m_avcodec_ctx->width, m_avcodec_ctx->height, 1 ); if ( required_size <= in_buff.size ) m_out_bufers[ m_buf_idx ] = in_buff.data; Thanks cco ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user
Re: [Libav-user] Suggest how to propery fill incomming AVFrame pointer in a decoder !
What is the difference between *av_frame_get_buffer* and *av_image_alloc* function ? Cause using anyone of 'em, I am getting the same output ! -- View this message in context: http://libav-users.943685.n4.nabble.com/Libav-user-Suggest-how-to-propery-fill-incomming-AVFrame-pointer-in-a-decoder-tp4662417p4662426.html Sent from the libav-users mailing list archive at Nabble.com. ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user
Re: [Libav-user] imgutils.h decode dst buffer going from avpicture_fill to av_image_fill_arrays
For example let suppose "decoder->dst_data[0]" has YUV buffer and its alignment is 1. --- //Allocate AVFrame data and linesize av_image_alloc(avframe->data, avframe->linesize, decoder->video_resolution.frame_width, decoder->video_resolution.frame_height, AV_PIX_FMT_YUV420P, 1); Below are the 3 methods to fill data array of avframe. --- //1) if your Y, U, V buffers are contiguous and have the correct size, This is deprecated avpicture_fill((AVPicture*) avframe, decoder->dst_data[0], avframe->format, avframe->width, avframe->height); --- //2) if your Y, U, V buffers are non-contiguous, This is deprecated // Initialize avframe->linesize avpicture_fill((AVPicture*) avframe, NULL, avframe->format, avframe->width, avframe->height); //Set avframe->data pointers manually avframe->data[0] = decoder->dst_data[0];//Y-Buffer avframe->data[1] = decoder->dst_data[1];//U-Buffer avframe->data[2] = decoder->dst_data[2];//V-Buffer --- //3) Fill data array of avframe, as decoder->dst_data[0] alignment is 1 use the same alignment. av_image_fill_arrays(avframe->data, avframe->linesize, decoder->dst_data[0], avframe->format, avframe->width, avframe->height, *1*); -- View this message in context: http://libav-users.943685.n4.nabble.com/Libav-user-imgutils-h-decode-dst-buffer-going-from-avpicture-fill-to-av-image-fill-arrays-tp4662419p4662425.html Sent from the libav-users mailing list archive at Nabble.com. ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user
