[FFmpeg-devel] [PATCH] Add support for demuxing the combined TrueHD/AC3 tracks in Blu-Ray m2ts files

[Baptiste Coudurier]

On 9/29/09 2:30 AM, Ian Caulfield wrote:
> This patch allows the combined TrueHD/AC3 tracks on Blu-Ray discs to be
> demuxed as two separate streams.
>
> Updated version that doesn't fudge the stream id of the AC3 track - both
>   streams will have the PID as the stream id.
>

I also find this very ugly, but I guess we do not have any other way of 
doing it.

I'm fine with the patch, though I think I like better sub_st and sub_pes 
instead of st2 and pes2, if you are ok with that.

 > [...]
 >
> @@ -584,6 +587,27 @@ static AVStream *new_pes_av_stream(PESContext *pes, uint32_t prog_reg_desc, uint
>           }
>       }
>
> +    // HDMV TrueHD streams also contain an AC3 coded version of the
> +    // audio track - add a second stream for this
> +    if (prog_reg_desc == AV_RL32("HDMV")&&  pes->stream_type == 0x83) {
> +        // priv_data cannot be shered between streams
> +        PESContext *pes2 = av_malloc(sizeof(PESContext));
> +        memcpy(pes2, pes, sizeof(PESContext));

sizeof(*pes2);

And put the code under the first if (prog_reg_desc == AV_RL32("HDMV"))

> +        if (pes2) {
> +            AVStream *st2 = av_new_stream(pes->stream, pes2->pid);
> +

pes->pid seems more logicical

> +            if (st2) {
> +                av_set_pts_info(st2, 33, 1, 90000);
> +                st2->priv_data = pes2;
> +                st2->codec->codec_type = CODEC_TYPE_AUDIO;
> +                st2->codec->codec_id   = CODEC_ID_AC3;
> +                st2->need_parsing = AVSTREAM_PARSE_FULL;
> +                pes2->st2 = pes->st2 = st2;
> +            } else
> +                av_free(pes2);

Can we continue with pes->st2 not set but pes->st set ?
If not pes->st should be freed also.

if (!st2) {
     av_free(pes2);
     return NULL;
}

Looks better IMHO.

 > [...]
 >
 > @@ -592,7 +616,7 @@ static void pmt_cb(MpegTSFilter *filter, const
 >       MpegTSContext *ts = filter->u.section_filter.opaque;
 >       SectionHeader h1, *h =&h1;
 >       PESContext *pes;
 > -    AVStream *st;
 > +    AVStream *st, *st2;
 >       const uint8_t *p, *p_end, *desc_list_end, *desc_end;
 >       int program_info_length, pcr_pid, pid, stream_type;
 >       int desc_list_len, desc_len, desc_tag;
 > @@ -730,6 +754,14 @@ static void pmt_cb(MpegTSFilter *filter, const
 >                   break;
 >               }
 >               p = desc_end;
 > +
 > +            if (prog_reg_desc == AV_RL32("HDMV")&&  stream_type == 0
 > +                st2 = pes->st2;
 > +                if (st2) {
 > +                    av_program_add_stream_index(ts->stream, h->id, s
 > +                    st2->codec->codec_tag = st->codec->codec_tag;
 > +                }
 > +            }
 >           }
 >           p = desc_list_end;

Is st2 variable really needed here ?

[...]

-- 
Baptiste COUDURIER
Key fingerprint                 8D77134D20CC9220201FC5DB0AC9325C5C1ABAAA
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