[Cin] possible cinepack profile speedup

[Andrew Randrianasulu]

I basically added

max_extra_cb_iterations=0
min_strips=3

this speedups encoder but quality is lower (not sure how much, was too
inpatient to wait for 1 min clip encode at 352*144 25 fps! with those
parameters ffmpeg encodes at nearly 3 fps, yay! In theory one can try to
set up renderfarm + number parallel  ffmpeg encoders, because encoder is
single threaded - but I haven't tested this)

also added two old (1996/8) h263 codecs - it theory they should be good for
low-cpu decoding (on emulated computers for example), but apparently h263
without 'p' only good at few pre-defined resolutions?

there is also speedhq.qt - for ffmpeg 4.4 (sadly ffmpeg can't encode video
with alpha, as this mpeg2-like format supports...)

sorry for not making progress on more important issues - I fiddled around
with overlayframe.h - but I can't see my addons working? Either bug in code
or I translated those blend modes wrongly..

there also two ffmpeg-4.4 patches recently added to git - they apply with
patch -p1 yet not with git apply patch (misformatted patch).. Adds avc
intra 300/480 if compiled against last x264 (15 june 2021)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20210629/9ae82f7f/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: h263.mov
Type: video/quicktime
Size: 9 bytes
Desc: not available
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20210629/9ae82f7f/attachment.mov>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: cinepak.qt
Type: video/quicktime
Size: 80 bytes
Desc: not available
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20210629/9ae82f7f/attachment.qt>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: h263p.mov
Type: video/quicktime
Size: 10 bytes
Desc: not available
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20210629/9ae82f7f/attachment-0001.mov>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: speedhq.qt
Type: video/quicktime
Size: 11 bytes
Desc: not available
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20210629/9ae82f7f/attachment-0001.qt>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ffmpeg-x264. patch1
Type: application/octet-stream
Size: 2172 bytes
Desc: not available
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20210629/9ae82f7f/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ffmpeg-x264. patch2
Type: application/octet-stream
Size: 624 bytes
Desc: not available
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20210629/9ae82f7f/attachment-0001.obj>