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Original commit message from CVS: * ext/jpeg/gstjpegdec.c: (gst_jpeg_dec_init), (gst_jpeg_dec_chain), (gst_jpeg_dec_change_state): * ext/jpeg/gstjpegdec.h: Fix crashes/invalid memory access for pictures that have a height that is not a multiple of 16 (or rather: v_samp_factor * DCTSIZE). Also fix the state change function for downwards state changes (need to chain up to parent before destroying our resources, to make sure pads get deactivated and our chain function isn't running and using those very same resources in another thread). The jpeg line buffer only needs to be v_samp_factor*DCTSIZE lines per plane, not picture_height lines; allocate that on the stack. |
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| .. | ||
| gstjpeg.c | ||
| gstjpegdec.c | ||
| gstjpegdec.h | ||
| gstjpegenc.c | ||
| gstjpegenc.h | ||
| gstsmokedec.c | ||
| gstsmokedec.h | ||
| gstsmokeenc.c | ||
| gstsmokeenc.h | ||
| Makefile.am | ||
| README | ||
| smokecodec.c | ||
| smokecodec.h | ||
| smokeformat.h | ||
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