mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-12-18 06:16:36 +00:00
37d98c27b9
Original commit message from CVS: * ext/jpeg/Makefile.am: * ext/jpeg/README: * ext/jpeg/gstjpeg.c: (plugin_init): * ext/jpeg/gstsmokedec.c: (gst_smokedec_get_type), (gst_smokedec_base_init), (gst_smokedec_class_init), (gst_smokedec_init), (gst_smokedec_link), (gst_smokedec_chain): * ext/jpeg/gstsmokedec.h: * ext/jpeg/gstsmokeenc.c: (gst_smokeenc_get_type), (gst_smokeenc_base_init), (gst_smokeenc_class_init), (gst_smokeenc_init), (gst_smokeenc_getcaps), (gst_smokeenc_link), (gst_smokeenc_resync), (gst_smokeenc_chain), (gst_smokeenc_set_property), (gst_smokeenc_get_property): * ext/jpeg/gstsmokeenc.h: * ext/jpeg/smokecodec.c: (smokecodec_init_destination), (smokecodec_flush_destination), (smokecodec_term_destination), (smokecodec_init_source), (smokecodec_fill_input_buffer), (smokecodec_skip_input_data), (smokecodec_resync_to_restart), (smokecodec_term_source), (smokecodec_encode_new), (smokecodec_decode_new), (smokecodec_info_free), (smokecodec_set_quality), (smokecodec_get_quality), (smokecodec_set_threshold), (smokecodec_get_threshold), (smokecodec_set_bitrate), (smokecodec_get_bitrate), (find_best_size), (abs_diff), (put), (smokecodec_encode), (smokecodec_parse_header), (smokecodec_decode): * ext/jpeg/smokecodec.h: Added a new simple jpeg based codec
20 lines
780 B
Text
20 lines
780 B
Text
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
|