[FFmpeg-devel] [PATCH 3/3] avcodec/xbmenc: Allow for making UW images

[Jose Da Silva]

I've run into some bugs where I was downloading a bunch of data and began 
seeing weird hiccups. For example, javascript promises to allow you to push 
some very long lines of data, but the hiccups I saw was with data larger 
than 2k in length (windows) pushed out of a child process stdout piped into 
the stdin of the calling parent program.
Soo much for smooth promises, this was broken and would run into similar 
problems on a linux PC with 32k line limits.
The solution was to break the data into smaller chunks than 2k - and then 
these data hiccups disappeared (windows PC).

It would be expected to be similar for linux PCs (32k I think) and other 
OSes with different sizes.

If the ANSI required minimum needs to be 509 chars or larger (assuming 
509+<CR>+<LF>+<0>=512), then 509 was chosen as the shortest worst-case 
scenario) in this patch.
Most small pictures will go output looking pretty much the same data out 
until you get to about 84bytes (672 pixels wide), where lines out begin to 
be split. For example a UW 4K will exceed a 2k readln and a UW 10K picture 
approaches an 8k readln

The purpose for this patch is to ensure that data remains below the 
readline limits (of 509 chars), so that programs (like javascript) can push 
data in large chunks without breaking into hiccups because the data length 
is too long to be pushed cleanly in one go.
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