From 5615f9dab4e7f911ce8799c34c0ca425b0e2a090 Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Tue, 26 Sep 2023 22:50:41 +0200 Subject: [PATCH] avcodec/wmaprodec: Avoid superfluous VLC structures For all VLCs here, the number of bits of the VLC is write-only, because it is hardcoded at the call site. Therefore one can replace these VLC structures with the only thing that is actually used: The pointer to the VLCElem table. And in most cases one can even avoid this. Signed-off-by: Andreas Rheinhardt --- libavcodec/wma.c | 4 +-- libavcodec/wma.h | 2 +- libavcodec/wmadec.c | 2 +- libavcodec/wmaprodec.c | 73 ++++++++++++++++++++++-------------------- 4 files changed, 43 insertions(+), 38 deletions(-) diff --git a/libavcodec/wma.c b/libavcodec/wma.c index 3b4d049a83..5eacf230fa 100644 --- a/libavcodec/wma.c +++ b/libavcodec/wma.c @@ -424,7 +424,7 @@ unsigned int ff_wma_get_large_val(GetBitContext *gb) * @return 0 on success, -1 otherwise */ int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb, - VLC *vlc, const float *level_table, + const VLCElem *vlc, const float *level_table, const uint16_t *run_table, int version, WMACoef *ptr, int offset, int num_coefs, int block_len, int frame_len_bits, @@ -435,7 +435,7 @@ int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb, uint32_t *iptr = (uint32_t *) ptr; const unsigned int coef_mask = block_len - 1; for (; offset < num_coefs; offset++) { - code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX); + code = get_vlc2(gb, vlc, VLCBITS, VLCMAX); if (code > 1) { /** normal code */ offset += run_table[code]; diff --git a/libavcodec/wma.h b/libavcodec/wma.h index 5dc604154d..3d0d872ea3 100644 --- a/libavcodec/wma.h +++ b/libavcodec/wma.h @@ -155,7 +155,7 @@ int ff_wma_total_gain_to_bits(int total_gain); int ff_wma_end(AVCodecContext *avctx); unsigned int ff_wma_get_large_val(GetBitContext *gb); int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb, - VLC *vlc, const float *level_table, + const VLCElem *vlc, const float *level_table, const uint16_t *run_table, int version, WMACoef *ptr, int offset, int num_coefs, int block_len, int frame_len_bits, diff --git a/libavcodec/wmadec.c b/libavcodec/wmadec.c index ab48e28ebc..3427e482dc 100644 --- a/libavcodec/wmadec.c +++ b/libavcodec/wmadec.c @@ -616,7 +616,7 @@ static int wma_decode_block(WMACodecContext *s) * there is potentially less energy there */ tindex = (ch == 1 && s->ms_stereo); memset(ptr, 0, s->block_len * sizeof(WMACoef)); - ret = ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex], + ret = ff_wma_run_level_decode(s->avctx, &s->gb, s->coef_vlc[tindex].table, s->level_table[tindex], s->run_table[tindex], 0, ptr, 0, nb_coefs[ch], s->block_len, s->frame_len_bits, coef_nb_bits); diff --git a/libavcodec/wmaprodec.c b/libavcodec/wmaprodec.c index 61b86ad6d1..65b269adda 100644 --- a/libavcodec/wmaprodec.c +++ b/libavcodec/wmaprodec.c @@ -132,12 +132,12 @@ #define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS) #define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS) -static VLC sf_vlc; ///< scale factor DPCM vlc -static VLC sf_rl_vlc; ///< scale factor run length vlc -static VLC vec4_vlc; ///< 4 coefficients per symbol -static VLC vec2_vlc; ///< 2 coefficients per symbol -static VLC vec1_vlc; ///< 1 coefficient per symbol -static VLC coef_vlc[2]; ///< coefficient run length vlc codes +static VLCElem sf_vlc[616]; ///< scale factor DPCM vlc +static VLCElem sf_rl_vlc[1406]; ///< scale factor run length vlc +static VLCElem vec4_vlc[604]; ///< 4 coefficients per symbol +static VLCElem vec2_vlc[562]; ///< 2 coefficients per symbol +static VLCElem vec1_vlc[562]; ///< 1 coefficient per symbol +static const VLCElem *coef_vlc[2]; ///< coefficient run length vlc codes static float sin64[33]; ///< sine table for decorrelation /** @@ -320,27 +320,32 @@ static av_cold int get_rate(AVCodecContext *avctx) static av_cold void decode_init_static(void) { - VLC_INIT_STATIC_FROM_LENGTHS(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE, - &scale_table[0][1], 2, - &scale_table[0][0], 2, 1, -60, 0, 616); - VLC_INIT_STATIC_FROM_LENGTHS(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE, - &scale_rl_table[0][1], 2, - &scale_rl_table[0][0], 2, 1, 0, 0, 1406); - VLC_INIT_STATIC_FROM_LENGTHS(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE, - coef0_lens, 1, - coef0_syms, 2, 2, 0, 0, 2108); - VLC_INIT_STATIC_FROM_LENGTHS(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE, + static VLCElem vlc_buf[2108 + 3912]; + VLCInitState state = VLC_INIT_STATE(vlc_buf); + + VLC_INIT_STATIC_TABLE_FROM_LENGTHS(sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE, + &scale_table[0][1], 2, + &scale_table[0][0], 2, 1, -60, 0); + VLC_INIT_STATIC_TABLE_FROM_LENGTHS(sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE, + &scale_rl_table[0][1], 2, + &scale_rl_table[0][0], 2, 1, 0, 0); + coef_vlc[0] = + ff_vlc_init_tables_from_lengths(&state, VLCBITS, HUFF_COEF0_SIZE, + coef0_lens, 1, + coef0_syms, 2, 2, 0, 0); + coef_vlc[1] = + ff_vlc_init_tables_from_lengths(&state, VLCBITS, HUFF_COEF1_SIZE, &coef1_table[0][1], 2, - &coef1_table[0][0], 2, 1, 0, 0, 3912); - VLC_INIT_STATIC_FROM_LENGTHS(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE, - vec4_lens, 1, - vec4_syms, 2, 2, -1, 0, 604); - VLC_INIT_STATIC_FROM_LENGTHS(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE, - &vec2_table[0][1], 2, - &vec2_table[0][0], 2, 1, -1, 0, 562); - VLC_INIT_STATIC_FROM_LENGTHS(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE, - &vec1_table[0][1], 2, - &vec1_table[0][0], 2, 1, 0, 0, 562); + &coef1_table[0][0], 2, 1, 0, 0); + VLC_INIT_STATIC_TABLE_FROM_LENGTHS(vec4_vlc, VLCBITS, HUFF_VEC4_SIZE, + vec4_lens, 1, + vec4_syms, 2, 2, -1, 0); + VLC_INIT_STATIC_TABLE_FROM_LENGTHS(vec2_vlc, VLCBITS, HUFF_VEC2_SIZE, + &vec2_table[0][1], 2, + &vec2_table[0][0], 2, 1, -1, 0); + VLC_INIT_STATIC_TABLE_FROM_LENGTHS(vec1_vlc, VLCBITS, HUFF_VEC1_SIZE, + &vec1_table[0][1], 2, + &vec1_table[0][0], 2, 1, 0, 0); /** calculate sine values for the decorrelation matrix */ for (int i = 0; i < 33; i++) @@ -929,7 +934,7 @@ static int decode_coeffs(WMAProDecodeCtx *s, int c) 0x41400000, 0x41500000, 0x41600000, 0x41700000, }; int vlctable; - VLC* vlc; + const VLCElem *vlc; WMAProChannelCtx* ci = &s->channel[c]; int rl_mode = 0; int cur_coeff = 0; @@ -940,7 +945,7 @@ static int decode_coeffs(WMAProDecodeCtx *s, int c) ff_dlog(s->avctx, "decode coefficients for channel %i\n", c); vlctable = get_bits1(&s->gb); - vlc = &coef_vlc[vlctable]; + vlc = coef_vlc[vlctable]; if (vlctable) { run = coef1_run; @@ -958,17 +963,17 @@ static int decode_coeffs(WMAProDecodeCtx *s, int c) int i; unsigned int idx; - idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH); + idx = get_vlc2(&s->gb, vec4_vlc, VLCBITS, VEC4MAXDEPTH); if ((int)idx < 0) { for (i = 0; i < 4; i += 2) { - idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH); + idx = get_vlc2(&s->gb, vec2_vlc, VLCBITS, VEC2MAXDEPTH); if ((int)idx < 0) { uint32_t v0, v1; - v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH); + v0 = get_vlc2(&s->gb, vec1_vlc, VLCBITS, VEC1MAXDEPTH); if (v0 == HUFF_VEC1_SIZE - 1) v0 += ff_wma_get_large_val(&s->gb); - v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH); + v1 = get_vlc2(&s->gb, vec1_vlc, VLCBITS, VEC1MAXDEPTH); if (v1 == HUFF_VEC1_SIZE - 1) v1 += ff_wma_get_large_val(&s->gb); vals[i ] = av_float2int(v0); @@ -1059,7 +1064,7 @@ static int decode_scale_factors(WMAProDecodeCtx* s) s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1; val = 45 / s->channel[c].scale_factor_step; for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) { - val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH); + val += get_vlc2(&s->gb, sf_vlc, SCALEVLCBITS, SCALEMAXDEPTH); *sf = val; } } else { @@ -1071,7 +1076,7 @@ static int decode_scale_factors(WMAProDecodeCtx* s) int val; int sign; - idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH); + idx = get_vlc2(&s->gb, sf_rl_vlc, VLCBITS, SCALERLMAXDEPTH); if (!idx) { uint32_t code = get_bits(&s->gb, 14);