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