diff options
author | Paul B Mahol <onemda@gmail.com> | 2016-12-26 18:58:46 +0300 |
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committer | Paul B Mahol <onemda@gmail.com> | 2017-01-07 00:05:45 +0300 |
commit | 90ac9f4094afc2aa7ee64a7b02df8fb05cbd7d8a (patch) | |
tree | 78650368c8133db9e79624d20ccf166a3adf09c2 /libavcodec/qdmc.c | |
parent | 49633f9f7498499d63391eb1351de66a8f603060 (diff) |
avcodec: add QDMC decoder
Signed-off-by: Paul B Mahol <onemda@gmail.com>
Diffstat (limited to 'libavcodec/qdmc.c')
-rw-r--r-- | libavcodec/qdmc.c | 783 |
1 files changed, 783 insertions, 0 deletions
diff --git a/libavcodec/qdmc.c b/libavcodec/qdmc.c new file mode 100644 index 0000000000..9560a3b5e1 --- /dev/null +++ b/libavcodec/qdmc.c @@ -0,0 +1,783 @@ +/* + * QDMC compatible decoder + * Copyright (c) 2017 Paul B Mahol + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <math.h> +#include <stddef.h> +#include <stdio.h> + +#define BITSTREAM_READER_LE + +#include "libavutil/channel_layout.h" + +#include "avcodec.h" +#include "bytestream.h" +#include "get_bits.h" +#include "internal.h" +#include "fft.h" + +typedef struct QDMCTone { + uint8_t mode; + uint8_t phase; + uint8_t offset; + int16_t freq; + int16_t amplitude; +} QDMCTone; + +typedef struct QDMCContext { + AVCodecContext *avctx; + + uint8_t frame_bits; + int band_index; + int frame_size; + int subframe_size; + int fft_offset; + int buffer_offset; + int nb_channels; + int checksum_size; + + uint8_t noise[2][19][16]; + QDMCTone tones[5][8192]; + int nb_tones[5]; + int cur_tone[5]; + float alt_sin[5][31]; + float fft_buffer[4][8192 * 2]; + float noise2_buffer[4096 * 2]; + float noise_buffer[4096 * 2]; + float buffer[2 * 32768]; + float *buffer_ptr; + int rndval; + + DECLARE_ALIGNED(32, FFTComplex, cmplx)[2][512]; + FFTContext fft_ctx; +} QDMCContext; + +static float sin_table[512]; +static VLC vtable[6]; + +static const unsigned code_prefix[] = { + 0x0, 0x1, 0x2, 0x3, 0x4, 0x6, 0x8, 0xA, + 0xC, 0x10, 0x14, 0x18, 0x1C, 0x24, 0x2C, 0x34, + 0x3C, 0x4C, 0x5C, 0x6C, 0x7C, 0x9C, 0xBC, 0xDC, + 0xFC, 0x13C, 0x17C, 0x1BC, 0x1FC, 0x27C, 0x2FC, 0x37C, + 0x3FC, 0x4FC, 0x5FC, 0x6FC, 0x7FC, 0x9FC, 0xBFC, 0xDFC, + 0xFFC, 0x13FC, 0x17FC, 0x1BFC, 0x1FFC, 0x27FC, 0x2FFC, 0x37FC, + 0x3FFC, 0x4FFC, 0x5FFC, 0x6FFC, 0x7FFC, 0x9FFC, 0xBFFC, 0xDFFC, + 0xFFFC, 0x13FFC, 0x17FFC, 0x1BFFC, 0x1FFFC, 0x27FFC, 0x2FFFC, 0x37FFC, + 0x3FFFC +}; + +static const float amplitude_tab[64] = { + 1.18750000f, 1.68359380f, 2.37500000f, 3.36718750f, 4.75000000f, + 6.73437500f, 9.50000000f, 13.4687500f, 19.0000000f, 26.9375000f, + 38.0000000f, 53.8750000f, 76.0000000f, 107.750000f, 152.000000f, + 215.500000f, 304.000000f, 431.000000f, 608.000000f, 862.000000f, + 1216.00000f, 1724.00000f, 2432.00000f, 3448.00000f, 4864.00000f, + 6896.00000f, 9728.00000f, 13792.0000f, 19456.0000f, 27584.0000f, + 38912.0000f, 55168.0000f, 77824.0000f, 110336.000f, 155648.000f, + 220672.000f, 311296.000f, 441344.000f, 622592.000f, 882688.000f, + 1245184.00f, 1765376.00f, 2490368.00f, 3530752.00f, 4980736.00f, + 7061504.00f, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, +}; + +static const uint16_t qdmc_nodes[112] = { + 0, 1, 2, 4, 6, 8, 12, 16, 24, 32, 48, 56, 64, + 80, 96, 120, 144, 176, 208, 240, 256, + 0, 2, 4, 8, 16, 24, 32, 48, 56, 64, 80, 104, + 128, 160, 208, 256, 0, 0, 0, 0, 0, + 0, 2, 4, 8, 16, 32, 48, 64, 80, 112, 160, 208, + 256, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 4, 8, 16, 32, 48, 64, 96, 144, 208, 256, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 4, 16, 32, 64, 256, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 +}; + +static const uint8_t noise_bands_size[] = { + 19, 14, 11, 9, 4, 2, 0 +}; + +static const uint8_t noise_bands_selector[] = { + 4, 3, 2, 1, 0, 0, 0, +}; + +static const uint8_t noise_value_bits[] = { + 12, 7, 9, 7, 10, 9, 11, 9, 9, 2, 9, 9, 9, 9, + 9, 3, 9, 10, 10, 12, 2, 3, 3, 5, 5, 6, 7, +}; + +static const uint8_t noise_value_symbols[] = { + 0, 10, 11, 12, 13, 14, 15, 16, 18, 1, 20, 22, 24, + 26, 28, 2, 30, 32, 34, 36, 3, 4, 5, 6, 7, 8, 9, +}; + +static const uint16_t noise_value_codes[] = { + 0xC7A, 0x002, 0x0FA, 0x03A, 0x35A, 0x1C2, 0x07A, 0x1FA, + 0x17A, 0x000, 0x0DA, 0x142, 0x0C2, 0x042, 0x1DA, 0x001, + 0x05A, 0x15A, 0x27A, 0x47A, 0x003, 0x005, 0x006, 0x012, + 0x00A, 0x022, 0x01A, +}; + +static const uint8_t noise_segment_length_bits[] = { + 10, 8, 5, 1, 2, 4, 4, 4, 6, 7, 9, 10, +}; + +static const uint8_t noise_segment_length_symbols[] = { + 0, 13, 17, 1, 2, 3, 4, 5, 6, 7, 8, 9, +}; + +static const uint16_t noise_segment_length_codes[] = { + 0x30B, 0x8B, 0x1B, 0x0, 0x1, 0x3, 0x7, 0xF, 0x2b, 0x4B, 0xB, 0x10B, +}; + +static const uint8_t freq_diff_bits[] = { + 18, 2, 4, 4, 5, 4, 4, 5, 5, 4, 5, 5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 6, + 7, 6, 6, 6, 7, 7, 7, 7, 7, 8, 9, 9, 8, 9, 11, 11, 12, 12, 13, 12, + 14, 15, 18, 16, 17, +}; + +static const uint32_t freq_diff_codes[] = { + 0x2AD46, 0x1, 0x0, 0x3, 0xC, 0xA, 0x7, 0x18, 0x12, 0xE, 0x4, 0x16, + 0xF, 0x1C, 0x8, 0x22, 0x26, 0x2, 0x3B, 0x34, 0x74, 0x1F, 0x14, 0x2B, + 0x1B, 0x3F, 0x28, 0x54, 0x6, 0x4B, 0xB, 0x68, 0xE8, 0x46, 0xC6, 0x1E8, + 0x146, 0x346, 0x546, 0x746, 0x1D46, 0xF46, 0xD46, 0x6D46, 0xAD46, 0x2D46, + 0x1AD46, +}; + +static const uint8_t amplitude_bits[] = { + 13, 7, 8, 9, 10, 10, 10, 10, 10, 9, 8, 7, 6, + 5, 4, 3, 3, 2, 3, 3, 4, 5, 7, 8, 9, 11, 12, 13, +}; + +static const uint16_t amplitude_codes[] = { + 0x1EC6, 0x6, 0xC2, 0x142, 0x242, 0x246, 0xC6, 0x46, 0x42, 0x146, 0xA2, + 0x62, 0x26, 0x16, 0xE, 0x5, 0x4, 0x3, 0x0, 0x1, 0xA, 0x12, 0x2, 0x22, + 0x1C6, 0x2C6, 0x6C6, 0xEC6, +}; + +static const uint8_t amplitude_diff_bits[] = { + 8, 2, 1, 3, 4, 5, 6, 7, 8, +}; + +static const uint8_t amplitude_diff_codes[] = { + 0xFE, 0x0, 0x1, 0x2, 0x6, 0xE, 0x1E, 0x3E, 0x7E, +}; + +static const uint8_t phase_diff_bits[] = { + 6, 2, 2, 4, 4, 6, 5, 4, 2, +}; + +static const uint8_t phase_diff_codes[] = { + 0x35, 0x2, 0x0, 0x1, 0xD, 0x15, 0x5, 0x9, 0x3, +}; + +#define INIT_VLC_STATIC_LE(vlc, nb_bits, nb_codes, \ + bits, bits_wrap, bits_size, \ + codes, codes_wrap, codes_size, \ + symbols, symbols_wrap, symbols_size, \ + static_size) \ + do { \ + static VLC_TYPE table[static_size][2]; \ + (vlc)->table = table; \ + (vlc)->table_allocated = static_size; \ + ff_init_vlc_sparse(vlc, nb_bits, nb_codes, \ + bits, bits_wrap, bits_size, \ + codes, codes_wrap, codes_size, \ + symbols, symbols_wrap, symbols_size, \ + INIT_VLC_LE | INIT_VLC_USE_NEW_STATIC); \ + } while (0) + +static av_cold void qdmc_init_static_data(AVCodec *codec) +{ + int i; + + INIT_VLC_STATIC_LE(&vtable[0], 12, FF_ARRAY_ELEMS(noise_value_bits), + noise_value_bits, 1, 1, noise_value_codes, 2, 2, noise_value_symbols, 1, 1, 4096); + INIT_VLC_STATIC_LE(&vtable[1], 10, FF_ARRAY_ELEMS(noise_segment_length_bits), + noise_segment_length_bits, 1, 1, noise_segment_length_codes, 2, 2, + noise_segment_length_symbols, 1, 1, 1024); + INIT_VLC_STATIC_LE(&vtable[2], 13, FF_ARRAY_ELEMS(amplitude_bits), + amplitude_bits, 1, 1, amplitude_codes, 2, 2, NULL, 0, 0, 8192); + INIT_VLC_STATIC_LE(&vtable[3], 18, FF_ARRAY_ELEMS(freq_diff_bits), + freq_diff_bits, 1, 1, freq_diff_codes, 4, 4, NULL, 0, 0, 262144); + INIT_VLC_STATIC_LE(&vtable[4], 8, FF_ARRAY_ELEMS(amplitude_diff_bits), + amplitude_diff_bits, 1, 1, amplitude_diff_codes, 1, 1, NULL, 0, 0, 256); + INIT_VLC_STATIC_LE(&vtable[5], 6, FF_ARRAY_ELEMS(phase_diff_bits), + phase_diff_bits, 1, 1, phase_diff_codes, 1, 1, NULL, 0, 0, 64); + + for (i = 0; i < 512; i++) + sin_table[i] = sin(2.0f * i * M_PI * 0.001953125f); +} + +static void make_noises(QDMCContext *s) +{ + int i, j, n0, n1, n2, diff; + float *nptr; + + for (j = 0; j < noise_bands_size[s->band_index]; j++) { + n0 = qdmc_nodes[j + 21 * s->band_index ]; + n1 = qdmc_nodes[j + 21 * s->band_index + 1]; + n2 = qdmc_nodes[j + 21 * s->band_index + 2]; + nptr = s->noise_buffer + 256 * j; + + for (i = 0; i + n0 < n1; i++, nptr++) + nptr[0] = i / (float)(n1 - n0); + + diff = n2 - n1; + nptr = s->noise_buffer + (j << 8) + n1 - n0; + + for (i = n1; i < n2; i++, nptr++, diff--) + nptr[0] = diff / (float)(n2 - n1); + } +} + +static av_cold int qdmc_decode_init(AVCodecContext *avctx) +{ + QDMCContext *s = avctx->priv_data; + int fft_size, fft_order, size, g, j, x; + GetByteContext b; + + if (!avctx->extradata || (avctx->extradata_size < 48)) { + av_log(avctx, AV_LOG_ERROR, "extradata missing or truncated\n"); + return AVERROR_INVALIDDATA; + } + + bytestream2_init(&b, avctx->extradata, avctx->extradata_size); + + while (bytestream2_get_bytes_left(&b) > 8) { + if (bytestream2_peek_be64(&b) == (((uint64_t)MKBETAG('f','r','m','a') << 32) | + (uint64_t)MKBETAG('Q','D','M','C'))) + break; + bytestream2_skipu(&b, 1); + } + bytestream2_skipu(&b, 8); + + if (bytestream2_get_bytes_left(&b) < 36) { + av_log(avctx, AV_LOG_ERROR, "not enough extradata (%i)\n", + bytestream2_get_bytes_left(&b)); + return AVERROR_INVALIDDATA; + } + + size = bytestream2_get_be32u(&b); + if (size > bytestream2_get_bytes_left(&b)) { + av_log(avctx, AV_LOG_ERROR, "extradata size too small, %i < %i\n", + bytestream2_get_bytes_left(&b), size); + return AVERROR_INVALIDDATA; + } + + if (bytestream2_get_be32u(&b) != MKBETAG('Q','D','C','A')) { + av_log(avctx, AV_LOG_ERROR, "invalid extradata, expecting QDCA\n"); + return AVERROR_INVALIDDATA; + } + bytestream2_skipu(&b, 4); + + avctx->channels = s->nb_channels = bytestream2_get_be32u(&b); + if (s->nb_channels <= 0 || s->nb_channels > 2) { + av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n"); + return AVERROR_INVALIDDATA; + } + avctx->channel_layout = avctx->channels == 2 ? AV_CH_LAYOUT_STEREO : + AV_CH_LAYOUT_MONO; + + avctx->sample_rate = bytestream2_get_be32u(&b); + avctx->bit_rate = bytestream2_get_be32u(&b); + bytestream2_skipu(&b, 4); + fft_size = bytestream2_get_be32u(&b); + fft_order = av_log2(fft_size) + 1; + s->checksum_size = bytestream2_get_be32u(&b); + if (s->checksum_size >= 1U << 28) { + av_log(avctx, AV_LOG_ERROR, "data block size too large (%u)\n", s->checksum_size); + return AVERROR_INVALIDDATA; + } + + if (avctx->sample_rate >= 32000) { + x = 28000; + s->frame_bits = 13; + } else if (avctx->sample_rate >= 16000) { + x = 20000; + s->frame_bits = 12; + } else { + x = 16000; + s->frame_bits = 11; + } + s->frame_size = 1 << s->frame_bits; + s->subframe_size = s->frame_size >> 5; + + if (avctx->channels == 2) + x = 3 * x / 2; + s->band_index = noise_bands_selector[FFMIN(6, llrint(floor(avctx->bit_rate * 3.0 / (double)x + 0.5)))]; + + if ((fft_order < 7) || (fft_order > 9)) { + avpriv_request_sample(avctx, "Unknown FFT order %d", fft_order); + return AVERROR_PATCHWELCOME; + } + + if (fft_size != (1 << (fft_order - 1))) { + av_log(avctx, AV_LOG_ERROR, "FFT size %d not power of 2.\n", fft_size); + return AVERROR_INVALIDDATA; + } + + ff_fft_init(&s->fft_ctx, fft_order, 1); + + avctx->sample_fmt = AV_SAMPLE_FMT_S16; + + for (g = 5; g > 0; g--) { + for (j = 0; j < (1 << g) - 1; j++) + s->alt_sin[5-g][j] = sin_table[(((j+1) << (8 - g)) & 0x1FF)]; + } + + make_noises(s); + + return 0; +} + +static av_cold int qdmc_decode_close(AVCodecContext *avctx) +{ + QDMCContext *s = avctx->priv_data; + + ff_fft_end(&s->fft_ctx); + + return 0; +} + +static int qdmc_get_vlc(GetBitContext *gb, VLC *table, int flag) +{ + int v; + + v = get_vlc2(gb, table->table, table->bits, 1); + if (v < 0) + return AVERROR_INVALIDDATA; + if (v) + v = v - 1; + else + v = get_bits(gb, get_bits(gb, 3) + 1); + + if (flag) { + if (v >= FF_ARRAY_ELEMS(code_prefix)) + return AVERROR_INVALIDDATA; + + v = code_prefix[v] + get_bitsz(gb, v >> 2); + } + + return v; +} + +static int skip_label(QDMCContext *s, GetBitContext *gb) +{ + uint32_t label = get_bits_long(gb, 32); + uint16_t sum = 226, checksum = get_bits(gb, 16); + const uint8_t *ptr = gb->buffer + 6; + int i; + + if (label != MKTAG('Q', 'M', 'C', 1)) + return AVERROR_INVALIDDATA; + + for (i = 0; i < s->checksum_size - 6; i++) + sum += ptr[i]; + + return sum != checksum; +} + +static int read_noise_data(QDMCContext *s, GetBitContext *gb) +{ + int ch, j, k, v, idx, band, lastval, newval, len; + + for (ch = 0; ch < s->nb_channels; ch++) { + for (band = 0; band < noise_bands_size[s->band_index]; band++) { + v = qdmc_get_vlc(gb, &vtable[0], 0); + if (v < 0) + return AVERROR_INVALIDDATA; + + if (v & 1) + v = v + 1; + else + v = -v; + + lastval = v / 2; + s->noise[ch][band][0] = lastval - 1; + for (j = 0; j < 15;) { + len = qdmc_get_vlc(gb, &vtable[1], 1); + if (len < 0) + return AVERROR_INVALIDDATA; + len += 1; + + v = qdmc_get_vlc(gb, &vtable[0], 0); + if (v < 0) + return AVERROR_INVALIDDATA; + + if (v & 1) + newval = lastval + (v + 1) / 2; + else + newval = lastval - v / 2; + + idx = j + 1; + if (len + idx > 16) + return AVERROR_INVALIDDATA; + + for (k = 1; idx <= j + len; k++, idx++) + s->noise[ch][band][idx] = lastval + k * (newval - lastval) / len - 1; + + lastval = newval; + j += len; + } + } + } + + return 0; +} + +static void add_tone(QDMCContext *s, int group, int offset, int freq, int stereo_mode, int amplitude, int phase) +{ + const int index = s->nb_tones[group]; + + if (index >= FF_ARRAY_ELEMS(s->tones[group])) { + av_log(s->avctx, AV_LOG_WARNING, "Too many tones already in buffer, ignoring tone!\n"); + return; + } + + s->tones[group][index].offset = offset; + s->tones[group][index].freq = freq; + s->tones[group][index].mode = stereo_mode; + s->tones[group][index].amplitude = amplitude; + s->tones[group][index].phase = phase; + s->nb_tones[group]++; +} + +static int read_wave_data(QDMCContext *s, GetBitContext *gb) +{ + int amp, phase, stereo_mode = 0, i, group, freq, group_size, group_bits; + int amp2, phase2, pos2, off; + + for (group = 0; group < 5; group++) { + group_size = 1 << (s->frame_bits - group - 1); + group_bits = 4 - group; + pos2 = 0; + off = 0; + + for (i = 1; ; i = freq + 1) { + int v; + + v = qdmc_get_vlc(gb, &vtable[3], 1); + if (v < 0) + return AVERROR_INVALIDDATA; + + freq = i + v; + while (freq >= group_size - 1) { + freq += 2 - group_size; + pos2 += group_size; + off += 1 << group_bits; + } + + if (pos2 >= s->frame_size) + break; + + if (s->nb_channels > 1) + stereo_mode = get_bits(gb, 2); + + amp = qdmc_get_vlc(gb, &vtable[2], 0); + if (amp < 0) + return AVERROR_INVALIDDATA; + phase = get_bits(gb, 3); + + if (stereo_mode > 1) { + amp2 = qdmc_get_vlc(gb, &vtable[4], 0); + if (amp2 < 0) + return AVERROR_INVALIDDATA; + amp2 = amp - amp2; + + phase2 = qdmc_get_vlc(gb, &vtable[5], 0); + if (phase2 < 0) + return AVERROR_INVALIDDATA; + phase2 = phase - phase2; + + if (phase2 < 0) + phase2 += 8; + } + + if ((freq >> group_bits) + 1 < s->subframe_size) { + add_tone(s, group, off, freq, stereo_mode & 1, amp, phase); + if (stereo_mode > 1) + add_tone(s, group, off, freq, ~stereo_mode & 1, amp2, phase2); + } + } + } + + return 0; +} + +static void lin_calc(QDMCContext *s, float amplitude, int node1, int node2, int index) +{ + int subframe_size, i, j, k, length; + float scale, *noise_ptr; + + scale = 0.5 * amplitude; + subframe_size = s->subframe_size; + if (subframe_size >= node2) + subframe_size = node2; + length = (subframe_size - node1) & 0xFFFC; + j = node1; + noise_ptr = &s->noise_buffer[256 * index]; + + for (i = 0; i < length; i += 4, j+= 4, noise_ptr += 4) { + s->noise2_buffer[j ] += scale * noise_ptr[0]; + s->noise2_buffer[j + 1] += scale * noise_ptr[1]; + s->noise2_buffer[j + 2] += scale * noise_ptr[2]; + s->noise2_buffer[j + 3] += scale * noise_ptr[3]; + } + + k = length + node1; + noise_ptr = s->noise_buffer + length + (index << 8); + for (i = length; i < subframe_size - node1; i++, k++, noise_ptr++) + s->noise2_buffer[k] += scale * noise_ptr[0]; +} + +static void add_noise(QDMCContext *s, int ch, int current_subframe) +{ + int i, j, aindex; + float amplitude; + float *im = &s->fft_buffer[0 + ch][s->fft_offset + s->subframe_size * current_subframe]; + float *re = &s->fft_buffer[2 + ch][s->fft_offset + s->subframe_size * current_subframe]; + + memset(s->noise2_buffer, 0, 4 * s->subframe_size); + + for (i = 0; i < noise_bands_size[s->band_index]; i++) { + if (qdmc_nodes[i + 21 * s->band_index] > s->subframe_size - 1) + break; + + aindex = s->noise[ch][i][current_subframe / 2]; + amplitude = aindex > 0 ? amplitude_tab[aindex & 0x3F] : 0.0f; + + lin_calc(s, amplitude, qdmc_nodes[21 * s->band_index + i], + qdmc_nodes[21 * s->band_index + i + 2], i); + } + + for (j = 2; j < s->subframe_size - 1; j++) { + float rnd_re, rnd_im; + + s->rndval = 214013 * s->rndval + 2531011; + rnd_im = ((s->rndval & 0x7FFF) - 16384.0f) * 0.000030517578f * s->noise2_buffer[j]; + s->rndval = 214013 * s->rndval + 2531011; + rnd_re = ((s->rndval & 0x7FFF) - 16384.0f) * 0.000030517578f * s->noise2_buffer[j]; + im[j ] += rnd_im; + re[j ] += rnd_re; + im[j+1] -= rnd_im; + re[j+1] -= rnd_re; + } +} + +static void add_wave(QDMCContext *s, int offset, int freqs, int group, int stereo_mode, int amp, int phase) +{ + int j, group_bits, pos, pindex; + float im, re, amplitude, level, *imptr, *reptr; + + if (s->nb_channels == 1) + stereo_mode = 0; + + group_bits = 4 - group; + pos = freqs >> (4 - group); + amplitude = amplitude_tab[amp & 0x3F]; + imptr = &s->fft_buffer[ stereo_mode][s->fft_offset + s->subframe_size * offset + pos]; + reptr = &s->fft_buffer[2 + stereo_mode][s->fft_offset + s->subframe_size * offset + pos]; + pindex = (phase << 6) - ((2 * (freqs >> (4 - group)) + 1) << 7); + for (j = 0; j < (1 << (group_bits + 1)) - 1; j++) { + pindex += (2 * freqs + 1) << (7 - group_bits); + level = amplitude * s->alt_sin[group][j]; + im = level * sin_table[ pindex & 0x1FF]; + re = level * sin_table[(pindex + 128) & 0x1FF]; + imptr[0] += im; + imptr[1] -= im; + reptr[0] += re; + reptr[1] -= re; + imptr += s->subframe_size; + reptr += s->subframe_size; + if (imptr >= &s->fft_buffer[stereo_mode][2 * s->frame_size]) { + imptr = &s->fft_buffer[0 + stereo_mode][pos]; + reptr = &s->fft_buffer[2 + stereo_mode][pos]; + } + } +} + +static void add_wave0(QDMCContext *s, int offset, int freqs, int stereo_mode, int amp, int phase) +{ + float level, im, re; + int pos; + + if (s->nb_channels == 1) + stereo_mode = 0; + + level = amplitude_tab[amp & 0x3F]; + im = level * sin_table[ (phase << 6) & 0x1FF]; + re = level * sin_table[((phase << 6) + 128) & 0x1FF]; + pos = s->fft_offset + freqs + s->subframe_size * offset; + s->fft_buffer[ stereo_mode][pos ] += im; + s->fft_buffer[2 + stereo_mode][pos ] += re; + s->fft_buffer[ stereo_mode][pos + 1] -= im; + s->fft_buffer[2 + stereo_mode][pos + 1] -= re; +} + +static void add_waves(QDMCContext *s, int current_subframe) +{ + int w, g; + + for (g = 0; g < 4; g++) { + for (w = s->cur_tone[g]; w < s->nb_tones[g]; w++) { + QDMCTone *t = &s->tones[g][w]; + + if (current_subframe < t->offset) + break; + add_wave(s, t->offset, t->freq, g, t->mode, t->amplitude, t->phase); + } + s->cur_tone[g] = w; + } + for (w = s->cur_tone[4]; w < s->nb_tones[4]; w++) { + QDMCTone *t = &s->tones[4][w]; + + if (current_subframe < t->offset) + break; + add_wave0(s, t->offset, t->freq, t->mode, t->amplitude, t->phase); + } + s->cur_tone[4] = w; +} + +static int decode_frame(QDMCContext *s, GetBitContext *gb, int16_t *out) +{ + int ret, ch, i, n; + + if (skip_label(s, gb)) + return AVERROR_INVALIDDATA; + + s->fft_offset = s->frame_size - s->fft_offset; + s->buffer_ptr = &s->buffer[s->nb_channels * s->buffer_offset]; + + ret = read_noise_data(s, gb); + if (ret < 0) + return ret; + + ret = read_wave_data(s, gb); + if (ret < 0) + return ret; + + for (n = 0; n < 32; n++) { + float *r; + + for (ch = 0; ch < s->nb_channels; ch++) + add_noise(s, ch, n); + + add_waves(s, n); + + for (ch = 0; ch < s->nb_channels; ch++) { + for (i = 0; i < s->subframe_size; i++) { + s->cmplx[ch][i].re = s->fft_buffer[ch + 2][s->fft_offset + n * s->subframe_size + i]; + s->cmplx[ch][i].im = s->fft_buffer[ch + 0][s->fft_offset + n * s->subframe_size + i]; + s->cmplx[ch][s->subframe_size + i].re = 0; + s->cmplx[ch][s->subframe_size + i].im = 0; + } + } + + for (ch = 0; ch < s->nb_channels; ch++) { + s->fft_ctx.fft_permute(&s->fft_ctx, s->cmplx[ch]); + s->fft_ctx.fft_calc(&s->fft_ctx, s->cmplx[ch]); + } + + r = &s->buffer_ptr[s->nb_channels * n * s->subframe_size]; + for (i = 0; i < 2 * s->subframe_size; i++) { + for (ch = 0; ch < s->nb_channels; ch++) { + *r++ += s->cmplx[ch][i].re; + } + } + + r = &s->buffer_ptr[n * s->subframe_size * s->nb_channels]; + for (i = 0; i < s->nb_channels * s->subframe_size; i++) { + out[i] = av_clipf(r[i], INT16_MIN, INT16_MAX); + } + out += s->subframe_size * s->nb_channels; + + for (ch = 0; ch < s->nb_channels; ch++) { + memset(s->fft_buffer[ch+0] + s->fft_offset + n * s->subframe_size, 0, 4 * s->subframe_size); + memset(s->fft_buffer[ch+2] + s->fft_offset + n * s->subframe_size, 0, 4 * s->subframe_size); + } + memset(s->buffer + s->nb_channels * (n * s->subframe_size + s->frame_size + s->buffer_offset), 0, 4 * s->subframe_size * s->nb_channels); + } + + s->buffer_offset += s->frame_size; + if (s->buffer_offset >= 32768 - s->frame_size) { + memcpy(s->buffer, &s->buffer[s->nb_channels * s->buffer_offset], 4 * s->frame_size * s->nb_channels); + s->buffer_offset = 0; + } + + return 0; +} + +static av_cold void qdmc_flush(AVCodecContext *avctx) +{ + QDMCContext *s = avctx->priv_data; + + memset(s->buffer, 0, sizeof(s->buffer)); + memset(s->fft_buffer, 0, sizeof(s->fft_buffer)); + s->fft_offset = 0; + s->buffer_offset = 0; +} + +static int qdmc_decode_frame(AVCodecContext *avctx, void *data, + int *got_frame_ptr, AVPacket *avpkt) +{ + QDMCContext *s = avctx->priv_data; + AVFrame *frame = data; + GetBitContext gb; + int ret; + + if (!avpkt->data) + return 0; + if (avpkt->size < s->checksum_size) + return AVERROR_INVALIDDATA; + + s->avctx = avctx; + frame->nb_samples = s->frame_size; + if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) + return ret; + + if ((ret = init_get_bits8(&gb, avpkt->data, s->checksum_size)) < 0) + return ret; + + memset(s->nb_tones, 0, sizeof(s->nb_tones)); + memset(s->cur_tone, 0, sizeof(s->cur_tone)); + + ret = decode_frame(s, &gb, (int16_t *)frame->data[0]); + if (ret >= 0) { + *got_frame_ptr = 1; + return s->checksum_size; + } + qdmc_flush(avctx); + return ret; +} + +AVCodec ff_qdmc_decoder = { + .name = "qdmc", + .long_name = NULL_IF_CONFIG_SMALL("QDesign Music Codec 1"), + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_QDMC, + .priv_data_size = sizeof(QDMCContext), + .init = qdmc_decode_init, + .init_static_data = qdmc_init_static_data, + .close = qdmc_decode_close, + .decode = qdmc_decode_frame, + .flush = qdmc_flush, + .capabilities = AV_CODEC_CAP_DR1, +}; |