avcodec/[e]ac3enc: Allow user-supplied buffers The size of the output buffer is always known in advance and the code has no alignment requirement (it uses mostly the PutBits API), so allowing user-supplied buffers is trivial. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Simplify AC-3 bit counting When encoding E-AC-3, whether coupling is on or not determines whether an additional frame based coupling exponent strategy element frmcplexpstr (of size five bits) is present in the bitstream. So just add five to the number of bits when counting them instead of adding 5*s->cpl_on (the latter field is currently only 0 or 1, so it doesn't make a difference). Furthermore, move some parts of the bit allocation that doesn't change per-frame to count_frame_bits_fixed() (which is only run once during init). Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

- [D] libavcodec/ac3enc.c

avcodec/[e]ac3enc: Fix indentation Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Avoid needlessly copying encoded packets around AC-3 and EAC-3 are codecs whose packet sizes are known in advance, so one can use the min_size parameter of ff_alloc_packet2() to allocate exactly this amount. This avoids a memcpy later in av_packet_make_refcounted() in encode_simple_internal(). Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Use actual size of buffer in init_put_bits() Since the very beginning (since de6d9b6404bfd1c589799142da5a95428f146edd) the AC-3 encoder used AC3_MAX_CODED_FRAME_SIZE (namely 3840) for the size of the output buffer (without any check at all). This causes problems when encoding EAC-3 for which the maximum is too small, smaller than the actual size of the buffer: One can run into asserts used by the PutBits API. Ticket #8513 is about such a case and this commit fixes it by using the real size of the buffer. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

- [D] libavcodec/ac3enc.c

lavc/ac3enc: rename variable to avoid shadowing Harmless, but confusing.

- [D] libavcodec/ac3enc.c

avcodec/ac3tab: Move ff_ac3_enc_channel_map to its only user and make it static. Reviewed-by: Lynne <dev@lynne.ee> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Share options and defaults Both AC-3 encoder share the same options, yet they are nevertheless duplicated in the binary; and the options applying to the EAC-3 encoder are a proper subset of the options for the AC-3 encoders, so that it can use the same options as the former by putting the options specific to AC-3 at the front. This commit implements this. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

- [D] libavcodec/ac3enc.c

ac3enc_fixed: convert to 32-bit sample format The AC3 encoder used to be a separate library called "Aften", which got merged into libavcodec (literally, SVN commits and all). The merge preserved as much features from the library as possible. The code had two versions - a fixed point version and a floating point version. FFmpeg had floating point DSP code used by other codecs, the AC3 decoder including, so the floating-point DSP was simply replaced with FFmpeg's own functions. However, FFmpeg had no fixed-point audio code at that point. So the encoder brought along its own fixed-point DSP functions, including a fixed-point MDCT. The fixed-point MDCT itself is trivially just a float MDCT with a different type and each multiply being a fixed-point multiply. So over time, it got refactored, and the FFT used for all other codecs was templated. Due to design decisions at the time, the fixed-point version of the encoder operates at 16-bits of precision. Although convenient, this, even at the time, was inadequate and inefficient. The encoder is noisy, does not produce output comparable to the float encoder, and even rings at higher frequencies due to the badly approximated winow function. Enter MIPS (owned by Imagination Technologies at the time). They wanted quick fixed-point decoding on their FPUless cores. So they contributed patches to template the AC3 decoder so it had both a fixed-point and a floating-point version. They also did the same for the AAC decoder. They however, used 32-bit samples. Not 16-bits. And we did not have 32-bit fixed-point DSP functions, including an MDCT. But instead of templating our MDCT to output 3 versions (float, 32-bit fixed and 16-bit fixed), they simply copy-pasted their own MDCT into ours, and completely ifdeffed our own MDCT code out if a 32-bit fixed point MDCT was selected. This is also the status quo nowadays - 2 separate MDCTs, one which produces floating point and 16-bit fixed point versions, and one sort-of integrated which produces 32-bit MDCT. MIPS weren't all that interested in encoding, so they left the encoder as-is, and they didn't care much about the ifdeffery, mess or quality - it's not their problem. So the MDCT/FFT code has always been a thorn in anyone looking to clean up code's eye. Backstory over. Internally AC3 operates on 25-bit fixed-point coefficients. So for the floating point version, the encoder simply runs the float MDCT, and converts the resulting coefficients to 25-bit fixed-point, as AC3 is inherently a fixed-point codec. For the fixed-point version, the input is 16-bit samples, so to maximize precision the frame samples are analyzed and the highest set bit is detected via ac3_max_msb_abs_int16(), and the coefficients are then scaled up via ac3_lshift_int16(), so the input for the FFT is always at least 14 bits, computed in normalize_samples(). After FFT, the coefficients are scaled up to 25 bits. This patch simply changes the encoder to accept 32-bit samples, reusing the already well-optimized 32-bit MDCT code, allowing us to clean up and drop a large part of a very messy code of ours, as well as prepare for the future lavu/tx conversion. The coefficients are simply scaled down to 25 bits during windowing, skipping 2 separate scalings, as the hacks to extend precision are simply no longer necessary. There's no point in running the MDCT always at 32 bits when you're going to drop 6 bits off anyway, the headroom is plenty, and the MDCT rounds properly. This also makes the encoder even slightly more accurate over the float version, as there's no coefficient conversion step necessary. SIZE SAVINGS: ARM32: HARDCODED TABLES: BASE - 10709590 DROP DSP - 10702872 - diff: -6.56KiB DROP MDCT - 10667932 - diff: -34.12KiB - both: -40.68KiB DROP FFT - 10336652 - diff: -323.52KiB - all: -364.20KiB SOFTCODED TABLES: BASE - 9685096 DROP DSP - 9678378 - diff: -6.56KiB DROP MDCT - 9643466 - diff: -34.09KiB - both: -40.65KiB DROP FFT - 9573918 - diff: -67.92KiB - all: -108.57KiB ARM64: HARDCODED TABLES: BASE - 14641112 DROP DSP - 14633806 - diff: -7.13KiB DROP MDCT - 14604812 - diff: -28.31KiB - both: -35.45KiB DROP FFT - 14286826 - diff: -310.53KiB - all: -345.98KiB SOFTCODED TABLES: BASE - 13636238 DROP DSP - 13628932 - diff: -7.13KiB DROP MDCT - 13599866 - diff: -28.38KiB - both: -35.52KiB DROP FFT - 13542080 - diff: -56.43KiB - all: -91.95KiB x86: HARDCODED TABLES: BASE - 12367336 DROP DSP - 12354698 - diff: -12.34KiB DROP MDCT - 12331024 - diff: -23.12KiB - both: -35.46KiB DROP FFT - 12029788 - diff: -294.18KiB - all: -329.64KiB SOFTCODED TABLES: BASE - 11358094 DROP DSP - 11345456 - diff: -12.34KiB DROP MDCT - 11321742 - diff: -23.16KiB - both: -35.50KiB DROP FFT - 11276946 - diff: -43.75KiB - all: -79.25KiB PERFORMANCE (10min random s32le): ARM32 - before - 39.9x - 0m15.046s ARM32 - after - 28.2x - 0m21.525s Speed: -30% ARM64 - before - 36.1x - 0m16.637s ARM64 - after - 36.0x - 0m16.727s Speed: -0.5% x86 - before - 184x - 0m3.277s x86 - after - 190x - 0m3.187s Speed: +3%

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Factor common end of float/fixed encode_frame out Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Set function pointers earlier Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

- [D] libavcodec/ac3enc.c

avcodec/[e]ac3enc: Make encoders init-threadsafe, fix race ff_eac3_exponent_init() set values twice when initializing a static table; ergo the initialization code must not run concurrently with a running EAC-3 encoder. Yet this code is executed every time an EAC-3 encoder is initialized. So use ff_thread_once() for this and also for a similar initialization performed for all AC-3 encoders to make them all init-threadsafe. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

- [D] libavcodec/ac3enc.c

lavu: move LOCAL_ALIGNED from internal.h to mem_internal.h That is a more appropriate place for it.

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: remove FF_ALLOCZ_ARRAY_OR_GOTO and gotos label Signed-off-by: Limin Wang <lance.lmwang@gmail.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: add FF_CODEC_CAP_INIT_CLEANUP Signed-off-by: Limin Wang <lance.lmwang@gmail.com>

- [D] libavcodec/ac3enc.c

ac3enc: fix AC3 downmix metadata issue Due to a typo, it was impossible to write 0.595 / -4.5 dB of ltrt_cmixlev, ltrt_surmixlev, loro_cmixlev, loro_surmixlev. Without any error 0.841 / -1.5 dB was written to file. Reviewed-by: Paul B Mahol <onemda@gmail.com> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

- [D] libavcodec/ac3enc.c

ac3enc: drop a global variable Log the warning message once per encoder instance instead. Reviewed-by: Kieran Kunhya <kierank@obe.tv> Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Signed-off-by: James Almer <jamrial@gmail.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Fix memleak Fixes ticket #8294. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

- [D] libavcodec/ac3enc.c

avcodec/ac3enc: Fix invalid shift Fixes the FATE-tests unknown_layout-ac3, ac3-fixed-encode, ac3-encode and eac3-encode. It furthermore fixes the ac3-encoder bugs mentioned in tickets #7994, #8144 and #8159. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

- [D] libavcodec/ac3enc.c

libavcodec: Reduce the size of some arrays This commit uses smaller types for some static const arrays to reduce their size in case the entries can be represented in the smaller type. The biggest savings came from inv_map_table in vp9.c. Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com> Signed-off-by: James Almer <jamrial@gmail.com>

- [D] libavcodec/ac3enc.c