From 909cfdc2059a53ffb55af3b9e0aadcaacae4a339 Mon Sep 17 00:00:00 2001 From: Martijn van Beurden Date: Tue, 11 Oct 2022 19:24:35 +0200 Subject: [PATCH] libavcodec/flacdec: Implement decoding of 32 bit-per-sample PCM Add decoding of FLAC files coding for 32 bit-per-sample PCM to libavcodec. --- libavcodec/flac.c | 4 +- libavcodec/flacdec.c | 218 +++++++++++++++++++++++++++++++++++++----- libavcodec/get_bits.h | 12 +++ libavcodec/mathops.h | 9 ++ 4 files changed, 219 insertions(+), 24 deletions(-) diff --git a/libavcodec/flac.c b/libavcodec/flac.c index 352d663c67..174b4801be 100644 --- a/libavcodec/flac.c +++ b/libavcodec/flac.c @@ -28,7 +28,7 @@ #include "flacdata.h" #include "flac_parse.h" -static const int8_t sample_size_table[] = { 0, 8, 12, 0, 16, 20, 24, 0 }; +static const int8_t sample_size_table[] = { 0, 8, 12, 0, 16, 20, 24, 32 }; static const AVChannelLayout flac_channel_layouts[8] = { AV_CHANNEL_LAYOUT_MONO, @@ -82,7 +82,7 @@ int ff_flac_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb, /* bits per sample */ bps_code = get_bits(gb, 3); - if (bps_code == 3 || bps_code == 7) { + if (bps_code == 3) { av_log(avctx, AV_LOG_ERROR + log_level_offset, "invalid sample size code (%d)\n", bps_code); diff --git a/libavcodec/flacdec.c b/libavcodec/flacdec.c index 5b8547a98f..cc778a8dff 100644 --- a/libavcodec/flacdec.c +++ b/libavcodec/flacdec.c @@ -64,6 +64,9 @@ typedef struct FLACContext { int32_t *decoded[FLAC_MAX_CHANNELS]; ///< decoded samples uint8_t *decoded_buffer; unsigned int decoded_buffer_size; + int64_t *decoded_33bps; ///< decoded samples for a 33 bps subframe + uint8_t *decoded_buffer_33bps; + unsigned int decoded_buffer_size_33bps; int buggy_lpc; ///< use workaround for old lavc encoded files FLACDSPContext dsp; @@ -154,6 +157,24 @@ static int allocate_buffers(FLACContext *s) s->stream_info.channels, s->stream_info.max_blocksize, AV_SAMPLE_FMT_S32P, 0); + if (ret >= 0 && s->stream_info.bps == 32 && s->stream_info.channels == 2) { + buf_size = av_samples_get_buffer_size(NULL, 1, + s->stream_info.max_blocksize, + AV_SAMPLE_FMT_S64P, 0); + if (buf_size < 0) + return buf_size; + + av_fast_malloc(&s->decoded_buffer_33bps, &s->decoded_buffer_size_33bps, buf_size); + if (!s->decoded_buffer_33bps) + return AVERROR(ENOMEM); + + ret = av_samples_fill_arrays((uint8_t **)&s->decoded_33bps, NULL, + s->decoded_buffer_33bps, + 1, + s->stream_info.max_blocksize, + AV_SAMPLE_FMT_S64P, 0); + + } return ret < 0 ? ret : 0; } @@ -331,6 +352,62 @@ static int decode_subframe_fixed(FLACContext *s, int32_t *decoded, return 0; } +#define DECODER_SUBFRAME_FIXED_WIDE(residual) { \ + const int blocksize = s->blocksize; \ + int ret; \ + \ + if ((ret = decode_residuals(s, residual, pred_order)) < 0) \ + return ret; \ + \ + switch (pred_order) { \ + case 0: \ + for (int i = pred_order; i < blocksize; i++) \ + decoded[i] = residual[i]; \ + break; \ + case 1: \ + for (int i = pred_order; i < blocksize; i++) \ + decoded[i] = (int64_t)residual[i] + (int64_t)decoded[i-1];\ + break; \ + case 2: \ + for (int i = pred_order; i < blocksize; i++) \ + decoded[i] = (int64_t)residual[i] + 2*(int64_t)decoded[i-1] - (int64_t)decoded[i-2]; \ + break; \ + case 3: \ + for (int i = pred_order; i < blocksize; i++) \ + decoded[i] = (int64_t)residual[i] + 3*(int64_t)decoded[i-1] - 3*(int64_t)decoded[i-2] + (int64_t)decoded[i-3]; \ + break; \ + case 4: \ + for (int i = pred_order; i < blocksize; i++) \ + decoded[i] = (int64_t)residual[i] + 4*(int64_t)decoded[i-1] - 6*(int64_t)decoded[i-2] + 4*(int64_t)decoded[i-3] - (int64_t)decoded[i-4]; \ + break; \ + default: \ + av_log(s->avctx, AV_LOG_ERROR, "illegal pred order %d\n", pred_order); \ + return AVERROR_INVALIDDATA; \ + } \ + return 0; \ +} + +static int decode_subframe_fixed_wide(FLACContext *s, int32_t *decoded, + int pred_order, int bps) +{ + /* warm up samples */ + for (int i = 0; i < pred_order; i++) { + decoded[i] = get_sbits_long(&s->gb, bps); + } + DECODER_SUBFRAME_FIXED_WIDE(decoded); +} + + +static int decode_subframe_fixed_33bps(FLACContext *s, int64_t *decoded, + int32_t *residual, int pred_order) +{ + /* warm up samples */ \ + for (int i = 0; i < pred_order; i++) { \ + decoded[i] = get_sbits64(&s->gb, 33); \ + } \ + DECODER_SUBFRAME_FIXED_WIDE(residual); +} + static void lpc_analyze_remodulate(SUINT32 *decoded, const int coeffs[32], int order, int qlevel, int len, int bps) { @@ -402,12 +479,53 @@ static int decode_subframe_lpc(FLACContext *s, int32_t *decoded, int pred_order, return 0; } +static int decode_subframe_lpc_33bps(FLACContext *s, int64_t *decoded, + int32_t *residual, int pred_order) +{ + int i, j, ret; + int coeff_prec, qlevel; + int coeffs[32]; + + /* warm up samples */ + for (i = 0; i < pred_order; i++) { + decoded[i] = get_sbits64(&s->gb, 33); + } + + coeff_prec = get_bits(&s->gb, 4) + 1; + if (coeff_prec == 16) { + av_log(s->avctx, AV_LOG_ERROR, "invalid coeff precision\n"); + return AVERROR_INVALIDDATA; + } + qlevel = get_sbits(&s->gb, 5); + if (qlevel < 0) { + av_log(s->avctx, AV_LOG_ERROR, "qlevel %d not supported, maybe buggy stream\n", + qlevel); + return AVERROR_INVALIDDATA; + } + + for (i = 0; i < pred_order; i++) { + coeffs[pred_order - i - 1] = get_sbits(&s->gb, coeff_prec); + } + + if ((ret = decode_residuals(s, residual, pred_order)) < 0) + return ret; + + for (i = pred_order; i < s->blocksize; i++, decoded++) { + int64_t sum = 0; + for (j = 0; j < pred_order; j++) + sum += (int64_t)coeffs[j] * decoded[j]; + decoded[j] = residual[i] + (sum >> qlevel); + } + + return 0; +} + static inline int decode_subframe(FLACContext *s, int channel) { int32_t *decoded = s->decoded[channel]; int type, wasted = 0; int bps = s->stream_info.bps; - int i, tmp, ret; + int i, ret; if (channel == 0) { if (s->ch_mode == FLAC_CHMODE_RIGHT_SIDE) @@ -427,7 +545,7 @@ static inline int decode_subframe(FLACContext *s, int channel) int left = get_bits_left(&s->gb); if ( left <= 0 || (left < bps && !show_bits_long(&s->gb, left)) || - !show_bits_long(&s->gb, bps)) { + !show_bits_long(&s->gb, bps-1)) { av_log(s->avctx, AV_LOG_ERROR, "Invalid number of wasted bits > available bits (%d) - left=%d\n", bps, left); @@ -436,34 +554,63 @@ static inline int decode_subframe(FLACContext *s, int channel) wasted = 1 + get_unary(&s->gb, 1, get_bits_left(&s->gb)); bps -= wasted; } - if (bps > 32) { - avpriv_report_missing_feature(s->avctx, "Decorrelated bit depth > 32"); - return AVERROR_PATCHWELCOME; - } //FIXME use av_log2 for types if (type == 0) { - tmp = get_sbits_long(&s->gb, bps); - for (i = 0; i < s->blocksize; i++) - decoded[i] = tmp; + if (bps < 33) { + int32_t tmp = get_sbits_long(&s->gb, bps); + for (i = 0; i < s->blocksize; i++) + decoded[i] = tmp; + } else { + int64_t tmp = get_sbits64(&s->gb, 33); + for (i = 0; i < s->blocksize; i++) + s->decoded_33bps[i] = tmp; + } } else if (type == 1) { - for (i = 0; i < s->blocksize; i++) - decoded[i] = get_sbits_long(&s->gb, bps); + if (bps < 33) { + for (i = 0; i < s->blocksize; i++) + decoded[i] = get_sbits_long(&s->gb, bps); + } else { + for (i = 0; i < s->blocksize; i++) + s->decoded_33bps[i] = get_sbits64(&s->gb, 33); + } } else if ((type >= 8) && (type <= 12)) { - if ((ret = decode_subframe_fixed(s, decoded, type & ~0x8, bps)) < 0) - return ret; + int order = type & ~0x8; + if (bps < 33) { + if (bps + order <= 32) { + if ((ret = decode_subframe_fixed(s, decoded, order, bps)) < 0) + return ret; + } else { + if ((ret = decode_subframe_fixed_wide(s, decoded, order, bps)) < 0) + return ret; + } + } else { + if ((ret = decode_subframe_fixed_33bps(s, s->decoded_33bps, decoded, order)) < 0) + return ret; + } } else if (type >= 32) { - if ((ret = decode_subframe_lpc(s, decoded, (type & ~0x20)+1, bps)) < 0) - return ret; + if (bps < 33) { + if ((ret = decode_subframe_lpc(s, decoded, (type & ~0x20)+1, bps)) < 0) + return ret; + } else { + if ((ret = decode_subframe_lpc_33bps(s, s->decoded_33bps, decoded, (type & ~0x20)+1)) < 0) + return ret; + } } else { av_log(s->avctx, AV_LOG_ERROR, "invalid coding type\n"); return AVERROR_INVALIDDATA; } - if (wasted && wasted < 32) { - int i; - for (i = 0; i < s->blocksize; i++) - decoded[i] = (unsigned)decoded[i] << wasted; + if (wasted) { + if (wasted+bps == 33) { + int i; + for (i = 0; i < s->blocksize; i++) + s->decoded_33bps[i] = (uint64_t)decoded[i] << wasted; + } else if (wasted < 32) { + int i; + for (i = 0; i < s->blocksize; i++) + decoded[i] = (unsigned)decoded[i] << wasted; + } } return 0; @@ -554,6 +701,26 @@ static int decode_frame(FLACContext *s) return 0; } +static void decorrelate_33bps(int ch_mode, int32_t **decoded, int64_t *decoded_33bps, int len) +{ + int i; + if (ch_mode == FLAC_CHMODE_LEFT_SIDE ) { + for (i = 0; i < len; i++) + decoded[1][i] = decoded[0][i] - decoded_33bps[i]; + } else if (ch_mode == FLAC_CHMODE_RIGHT_SIDE ) { + for (i = 0; i < len; i++) + decoded[0][i] = decoded[1][i] + decoded_33bps[i]; + } else if (ch_mode == FLAC_CHMODE_MID_SIDE ) { + for (i = 0; i < len; i++) { + uint64_t a = decoded[0][i]; + int64_t b = decoded_33bps[i]; + a -= b >> 1; + decoded[0][i] = (a + b); + decoded[1][i] = a; + } + } +} + static int flac_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *avpkt) { @@ -612,9 +779,15 @@ static int flac_decode_frame(AVCodecContext *avctx, AVFrame *frame, if ((ret = ff_thread_get_buffer(avctx, frame, 0)) < 0) return ret; - s->dsp.decorrelate[s->ch_mode](frame->data, s->decoded, - s->stream_info.channels, - s->blocksize, s->sample_shift); + if (s->stream_info.bps == 32 && s->ch_mode > 0) { + decorrelate_33bps(s->ch_mode, s->decoded, s->decoded_33bps, s->blocksize); + s->dsp.decorrelate[0](frame->data, s->decoded, s->stream_info.channels, + s->blocksize, s->sample_shift); + } else { + s->dsp.decorrelate[s->ch_mode](frame->data, s->decoded, + s->stream_info.channels, + s->blocksize, s->sample_shift); + } if (bytes_read > buf_size) { av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", bytes_read - buf_size); @@ -635,6 +808,7 @@ static av_cold int flac_decode_close(AVCodecContext *avctx) FLACContext *s = avctx->priv_data; av_freep(&s->decoded_buffer); + av_freep(&s->decoded_buffer_33bps); return 0; } diff --git a/libavcodec/get_bits.h b/libavcodec/get_bits.h index 992765dc92..52d13b8242 100644 --- a/libavcodec/get_bits.h +++ b/libavcodec/get_bits.h @@ -596,6 +596,18 @@ static inline int get_sbits_long(GetBitContext *s, int n) return sign_extend(get_bits_long(s, n), n); } +/** + * Read 0-64 bits as a signed integer. + */ +static inline int64_t get_sbits64(GetBitContext *s, int n) +{ + // sign_extend(x, 0) is undefined + if (!n) + return 0; + + return sign_extend64(get_bits64(s, n), n); +} + /** * Show 0-32 bits. */ diff --git a/libavcodec/mathops.h b/libavcodec/mathops.h index c89054d6ed..a1dc323304 100644 --- a/libavcodec/mathops.h +++ b/libavcodec/mathops.h @@ -138,6 +138,15 @@ static inline av_const int sign_extend(int val, unsigned bits) } #endif +#ifndef sign_extend64 +static inline av_const int64_t sign_extend64(int64_t val, unsigned bits) +{ + unsigned shift = 8 * sizeof(int64_t) - bits; + union { uint64_t u; int64_t s; } v = { (uint64_t) val << shift }; + return v.s >> shift; +} +#endif + #ifndef zero_extend static inline av_const unsigned zero_extend(unsigned val, unsigned bits) {