| /* |
| ** Copyright (C) 2007-2011 Erik de Castro Lopo <erikd@mega-nerd.com> |
| ** Copyright (c) 2007 <robs@users.sourceforge.net> |
| ** |
| ** This library 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 of the License, or (at |
| ** your option) any later version. |
| ** |
| ** This library 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 this library. If not, write to the Free Software Foundation, |
| ** Fifth Floor, 51 Franklin Street, Boston, MA 02111-1301, USA. |
| */ |
| |
| /* ADPCM: IMA, OKI <==> 16-bit PCM. */ |
| |
| #include "sfconfig.h" |
| |
| #include <string.h> |
| |
| /* Set up for libsndfile environment: */ |
| #include "common.h" |
| |
| #include "ima_oki_adpcm.h" |
| |
| #define MIN_SAMPLE -0x8000 |
| #define MAX_SAMPLE 0x7fff |
| |
| static int const ima_steps [] = /* ~16-bit precision */ |
| { 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 21, 23, 25, 28, 31, 34, 37, 41, 45, |
| 50, 55, 60, 66, 73, 80, 88, 97, 107, 118, 130, 143, 157, 173, 190, 209, 230, |
| 253, 279, 307, 337, 371, 408, 449, 494, 544, 598, 658, 724, 796, 876, 963, |
| 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, 3327, |
| 3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132, 7845, 8630, 9493, 10442, |
| 11487, 12635, 13899, 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, |
| 32767 |
| } ; |
| |
| static int const oki_steps [] = /* ~12-bit precision */ |
| { 256, 272, 304, 336, 368, 400, 448, 496, 544, 592, 656, 720, 800, 880, 960, |
| 1056, 1168, 1280, 1408, 1552, 1712, 1888, 2080, 2288, 2512, 2768, 3040, 3344, |
| 3680, 4048, 4464, 4912, 5392, 5936, 6528, 7184, 7904, 8704, 9568, 10528, |
| 11584, 12736, 14016, 15408, 16960, 18656, 20512, 22576, 24832 |
| } ; |
| |
| static int const step_changes [] = { -1, -1, -1, -1, 2, 4, 6, 8 } ; |
| |
| void |
| ima_oki_adpcm_init (IMA_OKI_ADPCM * state, IMA_OKI_ADPCM_TYPE type) |
| { |
| memset (state, 0, sizeof (*state)) ; |
| |
| if (type == IMA_OKI_ADPCM_TYPE_IMA) |
| { state->max_step_index = ARRAY_LEN (ima_steps) - 1 ; |
| state->steps = ima_steps ; |
| state->mask = (~0) ; |
| } |
| else |
| { state->max_step_index = ARRAY_LEN (oki_steps) - 1 ; |
| state->steps = oki_steps ; |
| state->mask = (~0) << 4 ; |
| } ; |
| |
| } /* ima_oki_adpcm_init */ |
| |
| |
| int |
| adpcm_decode (IMA_OKI_ADPCM * state, int code) |
| { int s ; |
| |
| s = ((code & 7) << 1) | 1 ; |
| s = ((state->steps [state->step_index] * s) >> 3) & state->mask ; |
| |
| if (code & 8) |
| s = -s ; |
| s += state->last_output ; |
| |
| if (s < MIN_SAMPLE || s > MAX_SAMPLE) |
| { int grace ; |
| |
| grace = (state->steps [state->step_index] >> 3) & state->mask ; |
| |
| if (s < MIN_SAMPLE - grace || s > MAX_SAMPLE + grace) |
| state->errors ++ ; |
| |
| s = s < MIN_SAMPLE ? MIN_SAMPLE : MAX_SAMPLE ; |
| } ; |
| |
| state->step_index += step_changes [code & 7] ; |
| state->step_index = SF_MIN (SF_MAX (state->step_index, 0), state->max_step_index) ; |
| state->last_output = s ; |
| |
| return s ; |
| } /* adpcm_decode */ |
| |
| int |
| adpcm_encode (IMA_OKI_ADPCM * state, int sample) |
| { int delta, sign = 0, code ; |
| |
| delta = sample - state->last_output ; |
| |
| if (delta < 0) |
| { sign = 8 ; |
| delta = -delta ; |
| } ; |
| |
| code = 4 * delta / state->steps [state->step_index] ; |
| code = sign | SF_MIN (code, 7) ; |
| adpcm_decode (state, code) ; /* Update encoder state */ |
| |
| return code ; |
| } /* adpcm_encode */ |
| |
| |
| void |
| ima_oki_adpcm_decode_block (IMA_OKI_ADPCM * state) |
| { unsigned char code ; |
| int k ; |
| |
| for (k = 0 ; k < state->code_count ; k++) |
| { code = state->codes [k] ; |
| state->pcm [2 * k] = adpcm_decode (state, code >> 4) ; |
| state->pcm [2 * k + 1] = adpcm_decode (state, code) ; |
| } ; |
| |
| state->pcm_count = 2 * k ; |
| } /* ima_oki_adpcm_decode_block */ |
| |
| |
| void |
| ima_oki_adpcm_encode_block (IMA_OKI_ADPCM * state) |
| { unsigned char code ; |
| int k ; |
| |
| /* |
| ** The codec expects an even number of input samples. |
| ** |
| ** Samples should always be passed in even length blocks. If the last block to |
| ** be encoded is odd length, extend that block by one zero valued sample. |
| */ |
| if (state->pcm_count % 2 == 1) |
| state->pcm [state->pcm_count ++] = 0 ; |
| |
| for (k = 0 ; k < state->pcm_count / 2 ; k++) |
| { code = adpcm_encode (state, state->pcm [2 * k]) << 4 ; |
| code |= adpcm_encode (state, state->pcm [2 * k + 1]) ; |
| state->codes [k] = code ; |
| } ; |
| |
| state->code_count = k ; |
| } /* ima_oki_adpcm_encode_block */ |
| |
| |
| #ifdef TEST |
| |
| static const unsigned char test_codes [] = |
| { 0x08, 0x08, 0x04, 0x7f, 0x72, 0xf7, 0x9f, 0x7c, 0xd7, 0xbc, 0x7a, 0xa7, 0xb8, |
| 0x4b, 0x0b, 0x38, 0xf6, 0x9d, 0x7a, 0xd7, 0xbc, 0x7a, 0xd7, 0xa8, 0x6c, 0x81, |
| 0x98, 0xe4, 0x0e, 0x7a, 0xd7, 0x9e, 0x7b, 0xc7, 0xab, 0x7a, 0x85, 0xc0, 0xb3, |
| 0x8f, 0x58, 0xd7, 0xad, 0x7a, 0xd7, 0xad, 0x7a, 0x87, 0xd0, 0x2b, 0x0e, 0x48, |
| 0xd7, 0xad, 0x78, 0xf7, 0xbc, 0x7a, 0xb7, 0xa8, 0x4b, 0x88, 0x18, 0xd5, 0x8d, |
| 0x6a, 0xa4, 0x98, 0x08, 0x00, 0x80, 0x88, |
| } ; |
| |
| static const short test_pcm [] = |
| { 32, 0, 32, 0, 32, 320, 880, -336, 2304, 4192, -992, 10128, 5360, -16352, |
| 30208, 2272, -31872, 14688, -7040, -32432, 14128, -1392, -15488, 22960, |
| 1232, -1584, 21488, -240, 2576, -15360, 960, -1152, -30032, 10320, 1008, |
| -30032, 16528, 1008, -30032, 16528, -5200, -30592, 15968, 448, -30592, |
| 15968, 448, -2368, 30960, 3024, -80, 8384, 704, -1616, -29168, -1232, 1872, |
| -32768, 13792, -1728, -32768, 13792, 4480, -32192, 14368, -7360, -32752, |
| 13808, -1712, -21456, 16992, 1472, -1344, 26848, -1088, 2016, -17728, 208, |
| -2112, -32768, 1376, -1728, -32768, 13792, -1728, -32768, 13792, -1728, |
| -32768, 13792, -1728, -32768, 13792, -1728, -4544, 32767, -1377, 1727, |
| 15823, -2113, 207, -27345, 591, -2513, -32768, 13792, -1728, -32768, 13792, |
| 10688, -31632, 14928, -6800, -32192, 14368, -1152, -20896, 17552, 2032, |
| -784, 22288, 560, -2256, -4816, 2176, 64, -21120, 9920, 6816, -24224, 16128, |
| 608, -13488, 9584, 272, -2544, 16, -2304, -192, 1728, -16, 1568, 128, -1184, |
| } ; |
| |
| |
| static void |
| test_oki_adpcm (void) |
| { |
| IMA_OKI_ADPCM adpcm ; |
| unsigned char code ; |
| int i, j ; |
| |
| printf (" Testing encoder : ") ; |
| fflush (stdout) ; |
| |
| ima_oki_adpcm_init (&adpcm, IMA_OKI_ADPCM_TYPE_OKI) ; |
| for (i = 0 ; i < ARRAY_LEN (test_codes) ; i++) |
| for (j = 0, code = test_codes [i] ; j < 2 ; j++, code <<= 4) |
| if (adpcm_decode (&adpcm, code >> 4) != test_pcm [2 * i + j]) |
| { printf ("\n\nFail at i = %d, j = %d.\n\n", i, j) ; |
| exit (1) ; |
| } ; |
| |
| puts ("ok") ; |
| |
| printf (" Testing decoder : ") ; |
| fflush (stdout) ; |
| |
| ima_oki_adpcm_init (&adpcm, IMA_OKI_ADPCM_TYPE_OKI) ; |
| for (i = 0 ; i < ARRAY_LEN (test_pcm) ; i += j) |
| { code = adpcm_encode (&adpcm, test_pcm [i]) ; |
| code = (code << 4) | adpcm_encode (&adpcm, test_pcm [i + 1]) ; |
| if (code != test_codes [i / 2]) |
| { printf ("\n\nFail at i = %d, %d should be %d\n\n", i, code, test_codes [i / 2]) ; |
| exit (1) ; |
| } ; |
| } ; |
| |
| puts ("ok") ; |
| } /* test_oki_adpcm */ |
| |
| static void |
| test_oki_adpcm_block (void) |
| { |
| IMA_OKI_ADPCM adpcm ; |
| int k ; |
| |
| if (ARRAY_LEN (adpcm.pcm) < ARRAY_LEN (test_pcm)) |
| { printf ("\n\nLine %d : ARRAY_LEN (adpcm->pcm) > ARRAY_LEN (test_pcm) (%d > %d).\n\n", __LINE__, ARRAY_LEN (adpcm.pcm), ARRAY_LEN (test_pcm)) ; |
| exit (1) ; |
| } ; |
| |
| if (ARRAY_LEN (adpcm.codes) < ARRAY_LEN (test_codes)) |
| { printf ("\n\nLine %d : ARRAY_LEN (adcodes->codes) > ARRAY_LEN (test_codes).n", __LINE__) ; |
| exit (1) ; |
| } ; |
| |
| printf (" Testing block encoder : ") ; |
| fflush (stdout) ; |
| |
| ima_oki_adpcm_init (&adpcm, IMA_OKI_ADPCM_TYPE_OKI) ; |
| |
| memcpy (adpcm.pcm, test_pcm, sizeof (adpcm.pcm [0]) * ARRAY_LEN (test_pcm)) ; |
| adpcm.pcm_count = ARRAY_LEN (test_pcm) ; |
| adpcm.code_count = 13 ; |
| |
| ima_oki_adpcm_encode_block (&adpcm) ; |
| |
| if (adpcm.code_count * 2 != ARRAY_LEN (test_pcm)) |
| { printf ("\n\nLine %d : %d * 2 != %d\n\n", __LINE__, adpcm.code_count * 2, ARRAY_LEN (test_pcm)) ; |
| exit (1) ; |
| } ; |
| |
| for (k = 0 ; k < ARRAY_LEN (test_codes) ; k++) |
| if (adpcm.codes [k] != test_codes [k]) |
| { printf ("\n\nLine %d : Fail at k = %d, %d should be %d\n\n", __LINE__, k, adpcm.codes [k], test_codes [k]) ; |
| exit (1) ; |
| } ; |
| |
| puts ("ok") ; |
| |
| printf (" Testing block decoder : ") ; |
| fflush (stdout) ; |
| |
| ima_oki_adpcm_init (&adpcm, IMA_OKI_ADPCM_TYPE_OKI) ; |
| |
| memcpy (adpcm.codes, test_codes, sizeof (adpcm.codes [0]) * ARRAY_LEN (test_codes)) ; |
| adpcm.code_count = ARRAY_LEN (test_codes) ; |
| adpcm.pcm_count = 13 ; |
| |
| ima_oki_adpcm_decode_block (&adpcm) ; |
| |
| if (adpcm.pcm_count != 2 * ARRAY_LEN (test_codes)) |
| { printf ("\n\nLine %d : %d * 2 != %d\n\n", __LINE__, adpcm.pcm_count, 2 * ARRAY_LEN (test_codes)) ; |
| exit (1) ; |
| } ; |
| |
| for (k = 0 ; k < ARRAY_LEN (test_pcm) ; k++) |
| if (adpcm.pcm [k] != test_pcm [k]) |
| { printf ("\n\nLine %d : Fail at i = %d, %d should be %d.\n\n", __LINE__, k, adpcm.pcm [k], test_pcm [k]) ; |
| exit (1) ; |
| } ; |
| |
| puts ("ok") ; |
| } /* test_oki_adpcm_block */ |
| |
| int |
| main (void) |
| { |
| test_oki_adpcm () ; |
| test_oki_adpcm_block () ; |
| |
| return 0 ; |
| } /* main */ |
| |
| #endif |