Chiebot-Mirror/FFmpeg - FFmpeg - Gitea: Git with a cup of tea

Author	SHA1	Message	Date
Rostislav Pehlivanov	d2ae5f77c6	aacenc: add SIMD optimizations for abs_pow34 and quantization Performance improvements: quant_bands: with: 681 decicycles in quant_bands, 8388453 runs, 155 skips without: 1190 decicycles in quant_bands, 8388386 runs, 222 skips Around 42% for the function Twoloop coder: abs_pow34: with/without: 7.82s/8.17s Around 4% for the entire encoder Both: with/without: 7.15s/8.17s Around 12% for the entire encoder Fast coder: abs_pow34: with/without: 3.40s/3.77s Around 10% for the entire encoder Both: with/without: 3.02s/3.77s Around 20% faster for the entire encoder Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com> Tested-by: Michael Niedermayer <michael@niedermayer.cc> Reviewed-by: James Almer <jamrial@gmail.com>	8 years ago
Rostislav Pehlivanov	4c5136a48b	aacenc_ltp: disable LTP with high lambda values Makes no sense to enable for high bitrates, the coder does well enough. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	9 years ago
Rostislav Pehlivanov	ed08cbd7b1	aacenc_ltp: fix out of bounds memory access Discovered by Coverity.	9 years ago
Rostislav Pehlivanov	f5b7a29ae8	aac_ltp: actually signal LTP as off during EIGHT_SHORT windows This hugely reduces the echo which was introduced with the previous commit (though likely because previously everything was broken). Makes LTP actually worthwhile now. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	9 years ago
Rostislav Pehlivanov	1e5dbb3409	aac_ltp: split, reorder and improve prediction algorithm This commit attempts to mirror what the decoder does more closely in addition to fixing some shortcomings.	9 years ago
Rostislav Pehlivanov	7303962f14	aacenc_ltp: adjust and speed up autocorrelation calculations There were some errors in the calculation as well as an entire unnecessary loop to find the gain coefficient. Merge the two loops. Thanks to @ubitux for the suggestions and testing.	9 years ago
Rostislav Pehlivanov	4c9805538d	aacenc_ltp: correct header description comment	9 years ago
Rostislav Pehlivanov	b0a3c614b4	aacenc_ltp: replace av_clip() with av_clip_uintp2() Suggested by ubitux. Convenient.	9 years ago
Rostislav Pehlivanov	780dba01f9	aacenc_ltp: fix assertion A value of 2048 will overflow 11 bits.	9 years ago
Rostislav Pehlivanov	27d23ae074	aacenc: add support for encoding files using Long Term Prediction Long Term Prediction allows for prediction of spectral coefficients via the previously decoded time-dependent samples. This feature works well with harmonic content 2 or more frames long, like speech, human or non-human, piano music or any constant tones at very low bitrates. It should be noted that the current coder is highly efficient and the rate control system is unable to encode files at extremely low bitrates (less than 14kbps seems to be impossible) so this extension isn't capable of optimum operation. Dramatic difference is observable with some types of audio and speech but for the most part the audiable differences are subtle. The spectrum looks better however so the encoder is able to harvest the additional bits that this feature provies, should the user choose to enable it. So it's best to enable this feature only if encoding at the absolutely lowest bitrate that the encoder is capable of.	9 years ago