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Diffstat (limited to 'contrib/ffmpeg/libavcodec/dpcm.c')
| -rw-r--r-- | contrib/ffmpeg/libavcodec/dpcm.c | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/dpcm.c b/contrib/ffmpeg/libavcodec/dpcm.c new file mode 100644 index 000000000..6243881de --- /dev/null +++ b/contrib/ffmpeg/libavcodec/dpcm.c @@ -0,0 +1,335 @@ +/* + * Assorted DPCM codecs + * Copyright (c) 2003 The ffmpeg Project. + * + * 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 + */ + +/** + * @file: dpcm.c + * Assorted DPCM (differential pulse code modulation) audio codecs + * by Mike Melanson (melanson@pcisys.net) + * Xan DPCM decoder by Mario Brito (mbrito@student.dei.uc.pt) + * for more information on the specific data formats, visit: + * http://www.pcisys.net/~melanson/codecs/simpleaudio.html + * SOL DPCMs implemented by Konstantin Shishkov + * + * Note about using the Xan DPCM decoder: Xan DPCM is used in AVI files + * found in the Wing Commander IV computer game. These AVI files contain + * WAVEFORMAT headers which report the audio format as 0x01: raw PCM. + * Clearly incorrect. To detect Xan DPCM, you will probably have to + * special-case your AVI demuxer to use Xan DPCM if the file uses 'Xxan' + * (Xan video) for its video codec. Alternately, such AVI files also contain + * the fourcc 'Axan' in the 'auds' chunk of the AVI header. + */ + +#include "avcodec.h" + +typedef struct DPCMContext { + int channels; + short roq_square_array[256]; + long sample[2];//for SOL_DPCM + const int *sol_table;//for SOL_DPCM +} DPCMContext; + +#define SATURATE_S16(x) if (x < -32768) x = -32768; \ + else if (x > 32767) x = 32767; +#define SE_16BIT(x) if (x & 0x8000) x -= 0x10000; + +static int interplay_delta_table[] = { + 0, 1, 2, 3, 4, 5, 6, 7, + 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, + 24, 25, 26, 27, 28, 29, 30, 31, + 32, 33, 34, 35, 36, 37, 38, 39, + 40, 41, 42, 43, 47, 51, 56, 61, + 66, 72, 79, 86, 94, 102, 112, 122, + 133, 145, 158, 173, 189, 206, 225, 245, + 267, 292, 318, 348, 379, 414, 452, 493, + 538, 587, 640, 699, 763, 832, 908, 991, + 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993, + 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008, + 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059, + 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206, + 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589, + -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1, + 1, 1, 5481, 10503, 15105, 19322, 23186, 26728, + 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298, + -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597, + -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772, + -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373, + -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180, + -1081, -991, -908, -832, -763, -699, -640, -587, + -538, -493, -452, -414, -379, -348, -318, -292, + -267, -245, -225, -206, -189, -173, -158, -145, + -133, -122, -112, -102, -94, -86, -79, -72, + -66, -61, -56, -51, -47, -43, -42, -41, + -40, -39, -38, -37, -36, -35, -34, -33, + -32, -31, -30, -29, -28, -27, -26, -25, + -24, -23, -22, -21, -20, -19, -18, -17, + -16, -15, -14, -13, -12, -11, -10, -9, + -8, -7, -6, -5, -4, -3, -2, -1 + +}; + +static const int sol_table_old[16] = + { 0x0, 0x1, 0x2 , 0x3, 0x6, 0xA, 0xF, 0x15, + -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0}; + +static const int sol_table_new[16] = + { 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15, + 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15}; + +static const int sol_table_16[128] = { + 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080, + 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120, + 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0, + 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230, + 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280, + 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0, + 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320, + 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370, + 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0, + 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480, + 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700, + 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00, + 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000 +}; + + + +static int dpcm_decode_init(AVCodecContext *avctx) +{ + DPCMContext *s = avctx->priv_data; + int i; + short square; + + s->channels = avctx->channels; + s->sample[0] = s->sample[1] = 0; + + switch(avctx->codec->id) { + + case CODEC_ID_ROQ_DPCM: + /* initialize square table */ + for (i = 0; i < 128; i++) { + square = i * i; + s->roq_square_array[i] = square; + s->roq_square_array[i + 128] = -square; + } + break; + + + case CODEC_ID_SOL_DPCM: + switch(avctx->codec_tag){ + case 1: + s->sol_table=sol_table_old; + s->sample[0] = s->sample[1] = 0x80; + break; + case 2: + s->sol_table=sol_table_new; + s->sample[0] = s->sample[1] = 0x80; + break; + case 3: + s->sol_table=sol_table_16; + break; + default: + av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n"); + return -1; + } + break; + + default: + break; + } + + return 0; +} + +static int dpcm_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + DPCMContext *s = avctx->priv_data; + int in, out = 0; + int predictor[2]; + int channel_number = 0; + short *output_samples = data; + int shift[2]; + unsigned char byte; + short diff; + + if (!buf_size) + return 0; + + switch(avctx->codec->id) { + + case CODEC_ID_ROQ_DPCM: + if (s->channels == 1) + predictor[0] = AV_RL16(&buf[6]); + else { + predictor[0] = buf[7] << 8; + predictor[1] = buf[6] << 8; + } + SE_16BIT(predictor[0]); + SE_16BIT(predictor[1]); + + /* decode the samples */ + for (in = 8, out = 0; in < buf_size; in++, out++) { + predictor[channel_number] += s->roq_square_array[buf[in]]; + SATURATE_S16(predictor[channel_number]); + output_samples[out] = predictor[channel_number]; + + /* toggle channel */ + channel_number ^= s->channels - 1; + } + break; + + case CODEC_ID_INTERPLAY_DPCM: + in = 6; /* skip over the stream mask and stream length */ + predictor[0] = AV_RL16(&buf[in]); + in += 2; + SE_16BIT(predictor[0]) + output_samples[out++] = predictor[0]; + if (s->channels == 2) { + predictor[1] = AV_RL16(&buf[in]); + in += 2; + SE_16BIT(predictor[1]) + output_samples[out++] = predictor[1]; + } + + while (in < buf_size) { + predictor[channel_number] += interplay_delta_table[buf[in++]]; + SATURATE_S16(predictor[channel_number]); + output_samples[out++] = predictor[channel_number]; + + /* toggle channel */ + channel_number ^= s->channels - 1; + } + + break; + + case CODEC_ID_XAN_DPCM: + in = 0; + shift[0] = shift[1] = 4; + predictor[0] = AV_RL16(&buf[in]); + in += 2; + SE_16BIT(predictor[0]); + if (s->channels == 2) { + predictor[1] = AV_RL16(&buf[in]); + in += 2; + SE_16BIT(predictor[1]); + } + + while (in < buf_size) { + byte = buf[in++]; + diff = (byte & 0xFC) << 8; + if ((byte & 0x03) == 3) + shift[channel_number]++; + else + shift[channel_number] -= (2 * (byte & 3)); + /* saturate the shifter to a lower limit of 0 */ + if (shift[channel_number] < 0) + shift[channel_number] = 0; + + diff >>= shift[channel_number]; + predictor[channel_number] += diff; + + SATURATE_S16(predictor[channel_number]); + output_samples[out++] = predictor[channel_number]; + + /* toggle channel */ + channel_number ^= s->channels - 1; + } + break; + case CODEC_ID_SOL_DPCM: + in = 0; + if (avctx->codec_tag != 3) { + while (in < buf_size) { + int n1, n2; + n1 = (buf[in] >> 4) & 0xF; + n2 = buf[in++] & 0xF; + s->sample[0] += s->sol_table[n1]; + if (s->sample[0] < 0) s->sample[0] = 0; + if (s->sample[0] > 255) s->sample[0] = 255; + output_samples[out++] = (s->sample[0] - 128) << 8; + s->sample[s->channels - 1] += s->sol_table[n2]; + if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0; + if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255; + output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8; + } + } else { + while (in < buf_size) { + int n; + n = buf[in++]; + if (n & 0x80) s->sample[channel_number] -= s->sol_table[n & 0x7F]; + else s->sample[channel_number] += s->sol_table[n & 0x7F]; + SATURATE_S16(s->sample[channel_number]); + output_samples[out++] = s->sample[channel_number]; + /* toggle channel */ + channel_number ^= s->channels - 1; + } + } + break; + } + + *data_size = out * sizeof(short); + return buf_size; +} + +AVCodec roq_dpcm_decoder = { + "roq_dpcm", + CODEC_TYPE_AUDIO, + CODEC_ID_ROQ_DPCM, + sizeof(DPCMContext), + dpcm_decode_init, + NULL, + NULL, + dpcm_decode_frame, +}; + +AVCodec interplay_dpcm_decoder = { + "interplay_dpcm", + CODEC_TYPE_AUDIO, + CODEC_ID_INTERPLAY_DPCM, + sizeof(DPCMContext), + dpcm_decode_init, + NULL, + NULL, + dpcm_decode_frame, +}; + +AVCodec xan_dpcm_decoder = { + "xan_dpcm", + CODEC_TYPE_AUDIO, + CODEC_ID_XAN_DPCM, + sizeof(DPCMContext), + dpcm_decode_init, + NULL, + NULL, + dpcm_decode_frame, +}; + +AVCodec sol_dpcm_decoder = { + "sol_dpcm", + CODEC_TYPE_AUDIO, + CODEC_ID_SOL_DPCM, + sizeof(DPCMContext), + dpcm_decode_init, + NULL, + NULL, + dpcm_decode_frame, +}; |