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

Author	SHA1	Message	Date
Andreas Rheinhardt	2668caf13c	avcodec/atrac3plus_data: Remove unused arrays Forgotten in `58fc810d42`. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>	4 years ago
Andreas Rheinhardt	2c3393d15d	avcodec/atrac3plus_data: Mark array as const Forgotten in `a7dbeb77c3`. Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>	4 years ago
Andreas Rheinhardt	58fc810d42	avcodec/atrac3plus: Run-length encode length tables to make them smaller This is very beneficial for the scale factor tables where 464+415 bytes of length information can be replaced by eight codebooks of 12 bytes each; furthermore the number of codes as well as the maximum length of a code can be easily derived from said codebooks, making tables containing said information superfluous. This and combining the symbols into one big array also made an array of pointers to the tables redundant. For the wordlen and code table tables the benefits are not that big (given these tables don't contain that many elements), but all in all using codebooks is also advantageouos for them. Therefore it has been done. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>	4 years ago
Andreas Rheinhardt	a7dbeb77c3	avcodec/atrac3plus: Combine codebooks into one array ATRAC3+ uses VLCs whose code lengths are ascending from left to right in the tree; ergo it is possible (and done) to run-length encode the lengths into so-called codebooks. These codebooks were variable-sized: The first byte contained the minimum length of a code, the second the maximum length; this was followed by max - min + 1 bytes containing the actual numbers. The minimal min was 1, the maximal max 12. While one saves a few bytes by only containing the range that is actually used, this is more than offset by the fact that there needs to be a pointer to each of these codebooks. Furthermore, since `5f8de7b741` the content of the Atrac3pSpecCodeTab structure (containing data for spectrum decoding) can be cleanly separated into fields that are only used during initialization and fields used during actual decoding: The pointers to the codebooks and the field indicating whether an earlier codebook should be reused constitute the former category. Therefore the new codebooks are not placed into the Atrac3pSpecCodeTab (which is now unused during init), but in an array of its own. The information whether an earlier codebook should be reused is encoded in the first number of each spectrum codebook: If it is negative, an earlier codebook (given by the number) should be reused. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>	4 years ago
Andreas Rheinhardt	1cf374c973	avcodec/atrac3plus: Combine symbols tables This allows to remove lots of pointers (130) to small symbol tables; it has the downside that some of the default tables must now be coded explicitly, but this costs only 6 + 4 + 8 + 16 + 8 bytes and is therefore dwarfed by the gains. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>	4 years ago
Andreas Rheinhardt	e27466d7e5	avcodec/atrac3plus: Make tables used to initialize VLCs smaller The ATRAC3+ decoder currently uses ff_init_vlc_sparse() to initialize several VLCs; sometimes a symbols table is used, sometimes not; some of the codes tables are uint16_t, some are uint8_t. Because of these two latter facts it makes sense to switch to ff_init_vlc_from_lengths() because it allows to remove the codes at the cost of adding symbols tables of type uint8_t in the cases where there were none before. Notice that sometimes the same codes and lengths tables were reused with two different symbols tables; this could have been preserved (meaning one could use a lengths table twice), but hasn't, because this allows to use only one pointer to both the symbols and lengths instead of two pointers. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>	4 years ago
Maxim Polijakowski	e6f0bb6527	ATRAC3+ decoder Cleanup by Diego Biurrun. Signed-off-by: Kostya Shishkov <kostya.shishkov@gmail.com>	11 years ago
Maxim Poliakovski	2e1fb96af3	ATRAC+ decoder Cleanup by Diego Biurrun. Signed-off-by: Michael Niedermayer <michaelni@gmx.at>	11 years ago