[gst-devel] h264parse srcpad buffers [NAL, SPS, PPS] ?? experts needed

[Marco Ballesio]

Hi,

On Tue, Mar 30, 2010 at 6:50 PM, ericcardmanNo3 <daniel.kuhne at yahoo.de> wrote:
>
> hi!
>
> i do:
> gst-launch filesrc location=my.264 ! h264parse ! myh264decoder !
> ffmpegcolorspace ! fbdevsink
>
> the filesrc passes buffers of 4096 byte to h264parse.
> h264parse passes a 23 byte buffer to myh264decoder where i decode to get
> stream configuration - works.
> But next buffer is 8 byte and i cant push the decoded buffer to downstream.
>
> 0:00:01.265381034  1526    0x7b388 DEBUG              h264parse
> gsth264parse.c:956:gst_h264_parse_sink_event:<h264parse0> Pushing newseg
> rate 1, applied rate 1, format 2, start 0, stop 3041866, pos 0
> 0:00:01.268311470  1526    0x7b388 DEBUG              h264parse
> gsth264parse.c:897:gst_h264_parse_chain:<h264parse0> received buffer of size
> 4096
> 0:00:01.269130929  1526    0x7b388 DEBUG              h264parse
> gsth264parse.c:499:gst_h264_parse_chain_forward:<h264parse0> NAL type: 7,
> ref_idc: 1

I think the problem here is that the parser returns ONLY an SPS and
your decoder is emitting a buffer after it.. as SPS/PPS contain only
metadata no meaningful (render-able) information can be emitted from
the decoder, so I'd rather ignore the output buffer which is indeed to
small to be rendered (unless you have a 3x2 pixels image).

>From my pov the parser is kind of misleading in many cases. You may
check on gst-dsp about how to avoid it.

Regards,
Marco

> 0:00:01.269879079  1526    0x7b388 DEBUG              h264parse
> gsth264parse.c:540:gst_h264_parse_chain_forward:<h264parse0> we have a SPS
> or PPS NAL
> 0:00:01.270759876  1526    0x7b388 DEBUG              h264parse
> gsth264parse.c:553:gst_h264_parse_chain_forward:<h264parse0> pushing buffer
> 0x432c0, size 23, ts 0:00:00.000000000
>
> --
> View this message in context: http://n4.nabble.com/h264parse-srcpad-buffers-NAL-SPS-PPS-experts-needed-tp1745406p1745406.html
> Sent from the GStreamer-devel mailing list archive at Nabble.com.
>
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