gstreamer

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History

Michael Olbrich 285811e7a7 jpegdec: be stricter when detecting interlaced video There are broken(?) mjpeg videos that are incorrectly detected as interlaced. This happens because 'info.height > height' (e.g. 1088 > 1080). In the interlaced case info.height is approximately 'height * 2' but not exactly because height is a multiple of DCTSIZE. Make the check more restrictive but take the rounding effect into account. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4696>		2023-05-25 18:34:34 +00:00
..
gstjpeg.c
gstjpeg.h
gstjpegdec.c	jpegdec: be stricter when detecting interlaced video	2023-05-25 18:34:34 +00:00
gstjpegdec.h
gstjpegelements.h
gstjpegenc.c
gstjpegenc.h
gstjpegplugin.c
gstsmokedec.c
gstsmokedec.h
gstsmokeenc.c
gstsmokeenc.h
meson.build	meson: Call pkgconfig.generate in the loop where we declare plugins dependencies	2022-09-01 21:17:35 +00:00
README
smokecodec.c
smokecodec.h
smokeformat.h

README

The Smoke Codec
---------------

This is a very simple compression algorithm I was toying with when doing a
Java based player. Decoding a JPEG in Java has acceptable speed so this codec
tries to exploit that feature. The algorithm first compares the last and the 
new image and finds all 16x16 blocks that have a squared difference bigger than
a configurable threshold. Then all these blocks are compressed into an NxM JPEG.
The quality of the JPEG is inversely proportional to the number of blocks, this
way, the picture quality degrades with heavy motion scenes but the bitrate stays
more or less constant.
Decoding decompresses the JPEG and then updates the old picture with the new
blocks.


TODO:
----
- make format extensible
- motion vectors
- do some real bitrate control