[FFmpeg-devel] [patch] export pmt and pcr pids from mpegts demuxer

[Baptiste Coudurier]

On 6/6/10 10:11 AM, Mike Scheutzow wrote:
> This patch allows a libav application to obtain the pmt pid(s) and pcr
> pid(s) values parsed by the mpegts demuxer. This is useful for
> applications that need the output stream pids to match the input stream
> pids.
>
> The pid values are added to AVProgram.metadata inside the AVFormatContext.
>
> Example: key="pmt_pid" value="129"
> key="pcr_pid" value="1064"
>
> Values are base10. This patch supports multiple programs per transport
> stream.
>
> Feedback appreciated.
>
>
> mpegts_export_psi_pids_v1.patch
>
>
> Index: libavformat/mpegts.c
> ===================================================================
> --- libavformat/mpegts.c	(revision 23373)
> +++ libavformat/mpegts.c	(working copy)
> @@ -863,6 +863,8 @@
>       int comp_page, anc_page;
>       char language[4];
>       uint32_t prog_reg_desc = 0; /* registration descriptor */
> +    AVProgram *program;
> +    char pcr_str[8];
>
>   #ifdef DEBUG
>       dprintf(ts->stream, "PMT: len %i\n", section_len);
> @@ -880,12 +882,23 @@
>       if (h->tid != PMT_TID)
>           return;
>
> +    /* returns existing if previously created */
> +    program = av_new_program(ts->stream, h->id);
> +    if (!program)
> +        return;
> +
>       clear_program(ts, h->id);
>       pcr_pid = get16(&p, p_end)&  0x1fff;
> -    if (pcr_pid<  0)
> +    if (pcr_pid<  0) {
> +        /* delete key if present */
> +        av_metadata_set2(&program->metadata, "pcr_pid", NULL, 0);
>           return;
> +    }
>       add_pid_to_pmt(ts, h->id, pcr_pid);
>
> +    snprintf(pcr_str, sizeof(pcr_str), "%d", pcr_pid);
> +    av_metadata_set2(&program->metadata, "pcr_pid", pcr_str, 0);
> +

Note to Michael:
Why did deprecate av_metadata_set already ? Having this useless 0 at the 
end is ulgy.

Patch looks good to me.

[...]

-- 
Baptiste COUDURIER
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