[FFmpeg-devel] [PATCH] movenc: write clap tag

[Derek Buitenhuis]

On 7/7/2017 3:20 AM, Dave Rice wrote:
> Resolves https://trac.ffmpeg.org/ticket/6145 and writes a clap atom that is coincident with the frames width and height.
> 
> 
> From 23d80d0d47829fed61e817b1e7c3f6d420c9ab5c Mon Sep 17 00:00:00 2001
> From: Dave Rice <dave at dericed.com>
> Date: Thu, 6 Jul 2017 21:12:38 -0400
> Subject: [PATCH] movenc: write clap tag
> 
> ---
>  libavformat/movenc.c | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)

Whoever pushes, add the ticket number into the commit message.

[...]

> +    avio_wb32(pb, 0); /* horizOff_N (= 0) */
> +    avio_wb32(pb, 1); /* horizOff_D (= 1) */
> +    avio_wb32(pb, 0); /* vertOff_N (= 0) */
> +    avio_wb32(pb, 1); /* vertOff_D (= 1) */

Near as I can tell, these related the active image area? Is it useful to ever set
this to anything but 0 (aka the whole image is active)? Was thinking of stuff like
analogue video, a la http://chromashift.org/aspectratio/. I assume the answer is
probably 'no'.

Patch itself LGTM.

- Derek