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663 lines
21 KiB
C
663 lines
21 KiB
C
#include "coding.h"
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/* LucasArts' iMUSE decoder, mainly for VIMA (like IMA but with variable frame and code sizes).
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* Reverse engineered from various .exe
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*
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* Info:
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* - https://github.com/scummvm/scummvm/blob/master/engines/scumm/imuse_digi/dimuse_codecs.cpp (V1)
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* - https://wiki.multimedia.cx/index.php/VIMA (V2)
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* - https://github.com/residualvm/residualvm/tree/master/engines/grim/imuse
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* https://github.com/residualvm/residualvm/tree/master/engines/grim/movie/codecs (V2)
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*/
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static const int16_t step_table[] = { /* same as IMA */
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7, 8, 9, 10, 11, 12, 13, 14,
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16, 17, 19, 21, 23, 25, 28, 31,
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34, 37, 41, 45, 50, 55, 60, 66,
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73, 80, 88, 97, 107, 118, 130, 143,
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157, 173, 190, 209, 230, 253, 279, 307,
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337, 371, 408, 449, 494, 544, 598, 658,
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724, 796, 876, 963, 1060, 1166, 1282, 1411,
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1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
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3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
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7132, 7845, 8630, 9493, 10442,11487,12635,13899,
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15289,16818,18500,20350,22385,24623,27086,29794,
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32767,
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};
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/* pre-calculated in V1:
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for (i = 0; i < 89; i++) {
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int counter = (4 * step_table[i] / 7) >> 1;
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int size = 1;
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while (counter > 0) {
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size++;
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counter >>= 1;
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}
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code_size_table[i] = clamp(size, 3, 8) - 1
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}
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*/
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static const uint8_t code_size_table_v1[89] = {
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2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6,
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6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
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7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
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};
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static const uint8_t code_size_table_v2[89] = {
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4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
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4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6,
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6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
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};
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static const int8_t index_table2b[4] = {
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-1, 4,
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-1, 4,
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};
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static const int8_t index_table3b_v1[8] = {
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-1,-1, 2, 8,
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-1,-1, 2, 8,
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};
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static const int8_t index_table3b_v2[8] = {
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-1,-1, 2, 6,
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-1,-1, 2, 6,
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};
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static const int8_t index_table4b[16] = {
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-1,-1,-1,-1, 1, 2, 4, 6,
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-1,-1,-1,-1, 1, 2, 4, 6,
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};
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static const int8_t index_table5b_v1[32] = {
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-1,-1,-1,-1,-1,-1,-1,-1, 1, 2, 4, 6, 8,12,16,32,
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-1,-1,-1,-1,-1,-1,-1,-1, 1, 2, 4, 6, 8,12,16,32,
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};
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static const int8_t index_table5b_v2[32] = {
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-1,-1,-1,-1,-1,-1,-1,-1, 1, 1, 1, 2, 2, 4, 5, 6,
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-1,-1,-1,-1,-1,-1,-1,-1, 1, 1, 1, 2, 2, 4, 5, 6,
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};
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static const int8_t index_table6b_v1[64] = {
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, 1, 2, 4, 6, 8,10,12,14, 16,18,20,22,24,26,28,32,
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, 1, 2, 4, 6, 8,10,12,14, 16,18,20,22,24,26,28,32,
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};
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static const int8_t index_table6b_v2[64] = {
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 5, 5, 6, 6,
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 5, 5, 6, 6,
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};
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static const int8_t index_table7b_v1[128] = {
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,
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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,
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,
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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,
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};
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static const int8_t index_table7b_v2[128] = {
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,
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1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6,
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-1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,
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1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6,
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};
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static const int8_t* index_tables_v1[8] = {
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NULL,
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NULL,
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index_table2b,
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index_table3b_v1,
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index_table4b,
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index_table5b_v1,
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index_table6b_v1,
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index_table7b_v1,
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};
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/* seems V2 doesn't actually use <4b, nor mirrored parts, even though they are defined */
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static const int8_t* index_tables_v2[8] = {
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NULL,
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NULL,
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index_table2b,
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index_table3b_v2,
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index_table4b,
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index_table5b_v2,
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index_table6b_v2,
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index_table7b_v2,
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};
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#define MAX_CHANNELS 2
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#define MAX_BLOCK_SIZE 0x2000
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#define MAX_BLOCK_COUNT 0x10000 /* arbitrary max */
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/* ************************** */
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typedef struct {
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/*const*/ int16_t* samples;
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int filled;
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int channels;
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//todo may be more useful with filled/full? use 2 mark methods?
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} sbuf_t;
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/* copy, move and mark consumed samples */
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static void sbuf_consume(sample_t** p_outbuf, int32_t* p_samples_to_do, sbuf_t* sbuf) {
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int samples_consume;
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samples_consume = *p_samples_to_do;
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if (samples_consume > sbuf->filled)
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samples_consume = sbuf->filled;
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/* memcpy is safe when filled/samples_copy is 0 (but must pass non-NULL bufs) */
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memcpy(*p_outbuf, sbuf->samples, samples_consume * sbuf->channels * sizeof(int16_t));
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sbuf->samples += samples_consume * sbuf->channels;
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sbuf->filled -= samples_consume;
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*p_outbuf += samples_consume * sbuf->channels;
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*p_samples_to_do -= samples_consume;
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}
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static int clamp_s32(int val, int min, int max) {
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if (val > max)
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return max;
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else if (val < min)
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return min;
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return val;
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}
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/* ************************** */
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typedef enum { COMP, MCMP } imuse_type_t;
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struct imuse_codec_data {
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/* config */
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imuse_type_t type;
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int channels;
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size_t block_count;
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struct block_entry_t {
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uint32_t offset; /* from file start */
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uint32_t size;
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uint32_t flags;
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uint32_t data;
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} *block_table;
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uint16_t adpcm_table[64 * 89];
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/* state */
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sbuf_t sbuf;
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int current_block;
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int16_t samples[MAX_BLOCK_SIZE / sizeof(int16_t) * MAX_CHANNELS];
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};
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imuse_codec_data* init_imuse(STREAMFILE* sf, int channels) {
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int i, j;
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off_t offset, data_offset;
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imuse_codec_data* data = NULL;
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if (channels > MAX_CHANNELS)
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goto fail;
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data = calloc(1, sizeof(struct imuse_codec_data));
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if (!data) goto fail;
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data->channels = channels;
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/* read index table */
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if (read_u32be(0x00,sf) == 0x434F4D50) { /* "COMP" */
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data->block_count = read_u32be(0x04,sf);
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if (data->block_count > MAX_BLOCK_COUNT) goto fail;
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/* 08: base codec? */
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/* 0c: some size? */
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data->block_table = calloc(data->block_count, sizeof(struct block_entry_t));
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if (!data->block_table) goto fail;
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offset = 0x10;
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for (i = 0; i < data->block_count; i++) {
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struct block_entry_t* entry = &data->block_table[i];
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entry->offset = read_u32be(offset + 0x00, sf);
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entry->size = read_u32be(offset + 0x04, sf);
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entry->flags = read_u32be(offset + 0x08, sf);
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/* 0x0c: null */
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entry->data = MAX_BLOCK_SIZE;
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/* blocks decode into fixed size, that may include header */
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if (entry->size > MAX_BLOCK_SIZE) {
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VGM_LOG("IMUSE: block size too big\n");
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goto fail;
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}
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if (entry->flags != 0x0D && entry->flags != 0x0F) { /* VIMA */
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VGM_LOG("IMUSE: unknown codec\n");
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goto fail; /* others are bunch of mini-codecs (ex. The Dig) */
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}
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offset += 0x10;
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}
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/* detect type */
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{
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uint32_t id = read_u32be(data->block_table[0].offset + 0x02, sf);
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if (id == 0x694D5553) { /* "iMUS" header [The Curse of Monkey Island (PC)] */
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data->type = COMP;
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} else {
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goto fail; /* no header [The Dig (PC)] */
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}
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}
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}
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else if (read_u32be(0x00,sf) == 0x4D434D50) { /* "MCMP" */
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data->block_count = read_u16be(0x04,sf);
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if (data->block_count > MAX_BLOCK_COUNT) goto fail;
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data->block_table = calloc(data->block_count, sizeof(struct block_entry_t));
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if (!data->block_table) goto fail;
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/* pre-calculate for simpler logic */
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data_offset = 0x06 + data->block_count * 0x09;
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data_offset += 0x02 + read_u16be(data_offset + 0x00, sf); /* mini text header */
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offset = 0x06;
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for (i = 0; i < data->block_count; i++) {
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struct block_entry_t* entry = &data->block_table[i];
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entry->flags = read_u8 (offset + 0x00, sf);
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entry->data = read_u32be(offset + 0x01, sf);
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entry->size = read_u32be(offset + 0x05, sf);
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entry->offset = data_offset;
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/* blocks of data and audio are separate */
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if (entry->data > MAX_BLOCK_SIZE || entry->size > MAX_BLOCK_SIZE) {
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VGM_LOG("IMUSE: block size too big\n");
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goto fail;
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}
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if (entry->flags != 0x00 && entry->flags != 0x01) { /* data or VIMA */
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VGM_LOG("IMUSE: unknown codec\n");
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goto fail;
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}
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offset += 0x09;
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data_offset += entry->size;
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}
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data->type = MCMP; /* with header [Grim Fandango (multi)] */
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/* there are iMUS or RIFF headers but affect parser */
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}
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else {
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goto fail;
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}
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/* iMUSE pre-calculates main decode ops as a table, looks similar to standard IMA expand */
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for (i = 0; i < 64; i++) {
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for (j = 0; j < 89; j++) {
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int counter = 32;
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int value = 0;
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int step = step_table[j];
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while (counter > 0) {
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if (counter & i)
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value += step;
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step >>= 1;
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counter >>= 1;
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}
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data->adpcm_table[i + j * 64] = value; /* non sequential: all 64 [0]s, [1]s ... [88]s */
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}
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}
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reset_imuse(data);
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return data;
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fail:
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free_imuse(data);
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return NULL;
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}
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/* **************************************** */
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static void decode_vima1(STREAMFILE* sf, sbuf_t* sbuf, uint8_t* buf, size_t data_left, int block_num, uint16_t* adpcm_table) {
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int ch, i, j, s;
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int bitpos;
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int adpcm_history[MAX_CHANNELS] = {0};
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int adpcm_step_index[MAX_CHANNELS] = {0};
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int chs = sbuf->channels;
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/* read header (outside decode in original code) */
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{
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int pos = 0;
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size_t copy_size;
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/* decodes BLOCK_SIZE bytes (not samples), including copy_size if exists, but not first 16b
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* or ADPCM headers. ADPCM setup must be set to 0 if headers weren't read. */
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copy_size = get_u16be(buf + pos);
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pos += 0x02;
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if (block_num == 0 && copy_size > 0) {
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/* iMUS header (always in first block) */
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pos += copy_size;
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data_left -= copy_size;
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}
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else if (copy_size > 0) {
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/* presumably PCM data (not seen) */
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for (i = 0, j = pos; i < copy_size / sizeof(sample_t); i++, j += 2) {
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sbuf->samples[i] = get_s16le(buf + j);
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}
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sbuf->filled += copy_size / chs / sizeof(sample_t);
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pos += copy_size;
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data_left -= copy_size;
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VGM_LOG("IMUS: found PCM block %i\n", block_num);
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}
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else {
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/* ADPCM header (never in first block) */
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for (i = 0; i < chs; i++) {
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adpcm_step_index[i] = get_u8 (buf + pos + 0x00);
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//adpcm_step[i] = get_s32be(buf + pos + 0x01); /* same as step_table[step_index] */
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adpcm_history[i] = get_s32be(buf + pos + 0x05);
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pos += 0x09;
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adpcm_step_index[i] = clamp_s32(adpcm_step_index[i], 0, 88); /* not originally */
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}
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}
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bitpos = pos * 8;
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}
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/* decode ADPCM data after header
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* (stereo layout: all samples from L, then all for R) */
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for (ch = 0; ch < chs; ch++) {
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int sample, step_index;
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int samples_to_do;
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int samples_left = data_left / sizeof(int16_t);
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int first_sample = sbuf->filled * chs + ch;
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if (chs == 1) {
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samples_to_do = samples_left;
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} else {
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/* L has +1 code for aligment in first block, must be read to reach R (code seems empty).
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* Not sure if COMI uses decoded bytes or decoded samples (returns samples_left / channels)
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* though but the latter makes more sense. */
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if (ch == 0)
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samples_to_do = (samples_left + 1) / chs;
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else
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samples_to_do = (samples_left + 0) / chs;
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}
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//;VGM_ASSERT((samples_left + 1) / 2 != (samples_left + 0) / 2, "IMUSE: sample diffs\n");
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step_index = adpcm_step_index[ch];
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sample = adpcm_history[ch];
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for (i = 0, s = first_sample; i < samples_to_do; i++, s += chs) {
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int code_size, code, sign_mask, data_mask, delta;
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if (bitpos >= MAX_BLOCK_SIZE * 8) {
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VGM_LOG("IMUSE: wrong bit offset\n");
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break;
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}
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code_size = code_size_table_v1[step_index];
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/* get bit thing from COMI (reads closest 16b then masks + shifts as needed), BE layout */
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code = get_u16be(buf + (bitpos >> 3)); //ok
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code = (code << (bitpos & 7)) & 0xFFFF;
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code = code >> (16 - code_size);
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bitpos += code_size;
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sign_mask = (1 << (code_size - 1));
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data_mask = sign_mask - 1; /* done with a LUT in COMI */
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delta = adpcm_table[(step_index * 64) + (((code & data_mask) << (7 - code_size)))];
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delta += step_table[step_index] >> (code_size - 1);
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if (code & sign_mask)
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delta = -delta;
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sample += delta;
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sample = clamp16(sample);
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sbuf->samples[s] = sample;
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step_index += index_tables_v1[code_size][code];
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step_index = clamp_s32(step_index, 0, 88);
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}
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}
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sbuf->filled += data_left / sizeof(int16_t) / chs;
|
|
}
|
|
|
|
static int decode_block1(STREAMFILE* sf, imuse_codec_data* data, uint8_t* block, size_t data_left) {
|
|
int block_num = data->current_block;
|
|
|
|
switch(data->block_table[block_num].flags) {
|
|
case 0x0D:
|
|
case 0x0F:
|
|
decode_vima1(sf, &data->sbuf, block, data_left, block_num, data->adpcm_table);
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static void decode_data2(STREAMFILE* sf, sbuf_t* sbuf, uint8_t* buf, size_t data_left, int block_num) {
|
|
int i, j;
|
|
int channels = sbuf->channels;
|
|
|
|
if (block_num == 0) {
|
|
/* iMUS header (always in first block, not shared with audio data unlike V1) */
|
|
sbuf->filled = 0;
|
|
}
|
|
else {
|
|
/* presumably PCM data (not seen) */
|
|
for (i = 0, j = 0; i < data_left / sizeof(sample_t); i++, j += 2) {
|
|
sbuf->samples[i] = get_s16le(buf + j);
|
|
}
|
|
sbuf->filled += data_left / channels / sizeof(sample_t);
|
|
|
|
VGM_LOG("IMUS: found PCM block %i\n", block_num);
|
|
}
|
|
}
|
|
|
|
static void decode_vima2(STREAMFILE* sf, sbuf_t* sbuf, uint8_t* buf, size_t data_left, uint16_t* adpcm_table) {
|
|
int ch, i, s;
|
|
int bitpos;
|
|
int adpcm_history[MAX_CHANNELS] = {0};
|
|
int adpcm_step_index[MAX_CHANNELS] = {0};
|
|
int chs = sbuf->channels;
|
|
uint16_t word;
|
|
int pos = 0;
|
|
|
|
|
|
/* read ADPCM header */
|
|
{
|
|
|
|
for (i = 0; i < chs; i++) {
|
|
adpcm_step_index[i] = get_u8 (buf + pos + 0x00);
|
|
adpcm_history[i] = get_s16be(buf + pos + 0x01);
|
|
pos += 0x03;
|
|
|
|
/* checked as < 0 and only for first index, means "stereo" */
|
|
if (adpcm_step_index[i] & 0x80) {
|
|
adpcm_step_index[i] = (~adpcm_step_index[i]) & 0xFF;
|
|
if (chs != 2) return;
|
|
}
|
|
|
|
/* not originally done but in case of garbage data */
|
|
adpcm_step_index[i] = clamp_s32(adpcm_step_index[i], 0, 88);
|
|
}
|
|
|
|
}
|
|
|
|
bitpos = 0;
|
|
word = get_u16be(buf + pos); /* originally with a rolling buf, use index to validate overflow */
|
|
pos += 0x02;
|
|
|
|
/* decode ADPCM data after header
|
|
* (stereo layout: all samples from L, then all for R) */
|
|
for (ch = 0; ch < chs; ch++) {
|
|
int sample, step_index;
|
|
int samples_to_do;
|
|
int samples_left = data_left / sizeof(int16_t);
|
|
int first_sample = sbuf->filled * chs + ch;
|
|
|
|
samples_to_do = samples_left / chs;
|
|
|
|
step_index = adpcm_step_index[ch];
|
|
sample = adpcm_history[ch];
|
|
|
|
for (i = 0, s = first_sample; i < samples_to_do; i++, s += chs) {
|
|
int code_size, code, sign_mask, data_mask, delta;
|
|
|
|
if (pos >= MAX_BLOCK_SIZE) {
|
|
VGM_LOG("IMUSE: wrong pos offset\n");
|
|
break;
|
|
}
|
|
|
|
code_size = code_size_table_v2[step_index];
|
|
sign_mask = (1 << (code_size - 1));
|
|
data_mask = (sign_mask - 1);
|
|
|
|
/* get bit thing, masks current code and moves 'upwards' word after reading 8 bits */
|
|
bitpos += code_size;
|
|
code = (word >> (16 - bitpos)) & (sign_mask | data_mask);
|
|
if (bitpos > 7) {
|
|
word = (word << 8) | buf[pos++];
|
|
bitpos -= 8;
|
|
}
|
|
|
|
/* clean sign stuff for next tests */
|
|
if (code & sign_mask)
|
|
code ^= sign_mask;
|
|
else
|
|
sign_mask = 0;
|
|
|
|
/* all bits set mean 'keyframe' = read next sample */
|
|
if (code == data_mask) {
|
|
sample = (int16_t)(word << bitpos);
|
|
word = (word << 8) | buf[pos++];
|
|
sample |= (word >> (8 - bitpos)) & 0xFF;
|
|
word = (word << 8) | buf[pos++];
|
|
}
|
|
else {
|
|
delta = adpcm_table[(step_index * 64) + ((code << (7 - code_size)))];
|
|
if (code)
|
|
delta += step_table[step_index] >> (code_size - 1);
|
|
if (sign_mask)
|
|
delta = -delta;
|
|
|
|
sample += delta;
|
|
sample = clamp16(sample);
|
|
}
|
|
|
|
sbuf->samples[s] = sample;
|
|
|
|
step_index += index_tables_v2[code_size][code];
|
|
step_index = clamp_s32(step_index, 0, 88);
|
|
}
|
|
}
|
|
|
|
sbuf->filled += data_left / sizeof(int16_t) / chs;
|
|
}
|
|
|
|
static int decode_block2(STREAMFILE* sf, imuse_codec_data* data, uint8_t* block, size_t data_left) {
|
|
int block_num = data->current_block;
|
|
|
|
switch(data->block_table[block_num].flags) {
|
|
case 0x00:
|
|
decode_data2(sf, &data->sbuf, block, data_left, block_num);
|
|
break;
|
|
|
|
case 0x01:
|
|
decode_vima2(sf, &data->sbuf, block, data_left, data->adpcm_table);
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
|
|
/* decodes a whole block into sample buffer, all at once due to L/R layout and VBR data */
|
|
static int decode_block(STREAMFILE* sf, imuse_codec_data* data) {
|
|
int ok;
|
|
uint8_t block[MAX_BLOCK_SIZE];
|
|
size_t data_left;
|
|
|
|
data->sbuf.samples = data->samples;
|
|
data->sbuf.channels = data->channels;
|
|
|
|
if (data->current_block >= data->block_count) {
|
|
return 0;
|
|
}
|
|
|
|
/* read block */
|
|
{
|
|
off_t offset = data->block_table[data->current_block].offset;
|
|
size_t size = data->block_table[data->current_block].size;
|
|
|
|
read_streamfile(block, offset, size, sf);
|
|
|
|
data_left = data->block_table[data->current_block].data;
|
|
}
|
|
|
|
switch(data->type) {
|
|
case COMP:
|
|
ok = decode_block1(sf, data, block, data_left);
|
|
break;
|
|
|
|
case MCMP:
|
|
ok = decode_block2(sf, data, block, data_left);
|
|
break;
|
|
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
/* block fully read */
|
|
data->current_block++;
|
|
|
|
return ok;
|
|
}
|
|
|
|
|
|
void decode_imuse(VGMSTREAM* vgmstream, sample_t* outbuf, int32_t samples_to_do) {
|
|
imuse_codec_data* data = vgmstream->codec_data;
|
|
STREAMFILE* sf = vgmstream->ch[0].streamfile;
|
|
int ok;
|
|
|
|
|
|
while (samples_to_do > 0) {
|
|
sbuf_t* sbuf = &data->sbuf;
|
|
|
|
if (sbuf->filled == 0) {
|
|
ok = decode_block(sf, data);
|
|
if (!ok) goto fail;
|
|
}
|
|
|
|
sbuf_consume(&outbuf, &samples_to_do, sbuf);
|
|
}
|
|
|
|
return;
|
|
fail:
|
|
//todo fill silence
|
|
return;
|
|
}
|
|
|
|
|
|
void free_imuse(imuse_codec_data* data) {
|
|
if (!data) return;
|
|
|
|
free(data->block_table);
|
|
free(data);
|
|
}
|
|
|
|
void seek_imuse(imuse_codec_data* data, int32_t num_sample) {
|
|
if (!data) return;
|
|
|
|
//todo find closest block, set skip count
|
|
|
|
reset_imuse(data);
|
|
}
|
|
|
|
void reset_imuse(imuse_codec_data* data) {
|
|
if (!data) return;
|
|
|
|
data->current_block = 0;
|
|
data->sbuf.filled = 0;
|
|
}
|