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https://github.com/Ryujinx/SDL.git
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e8677a1bd2
This is just enough to get you through a file that just used the extended header for float or int data. It doesn't handle all the other things that you expect from this header, like 24-bit samples inside a 32-bit container or speaker masks.
648 lines
20 KiB
C
648 lines
20 KiB
C
/*
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Simple DirectMedia Layer
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Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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*/
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#include "../SDL_internal.h"
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/* Microsoft WAVE file loading routines */
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#include "SDL_audio.h"
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#include "SDL_wave.h"
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static int ReadChunk(SDL_RWops * src, Chunk * chunk);
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struct MS_ADPCM_decodestate
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{
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Uint8 hPredictor;
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Uint16 iDelta;
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Sint16 iSamp1;
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Sint16 iSamp2;
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};
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static struct MS_ADPCM_decoder
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{
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WaveFMT wavefmt;
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Uint16 wSamplesPerBlock;
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Uint16 wNumCoef;
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Sint16 aCoeff[7][2];
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/* * * */
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struct MS_ADPCM_decodestate state[2];
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} MS_ADPCM_state;
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static int
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InitMS_ADPCM(WaveFMT * format)
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{
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Uint8 *rogue_feel;
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int i;
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/* Set the rogue pointer to the MS_ADPCM specific data */
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MS_ADPCM_state.wavefmt.encoding = SDL_SwapLE16(format->encoding);
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MS_ADPCM_state.wavefmt.channels = SDL_SwapLE16(format->channels);
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MS_ADPCM_state.wavefmt.frequency = SDL_SwapLE32(format->frequency);
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MS_ADPCM_state.wavefmt.byterate = SDL_SwapLE32(format->byterate);
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MS_ADPCM_state.wavefmt.blockalign = SDL_SwapLE16(format->blockalign);
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MS_ADPCM_state.wavefmt.bitspersample =
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SDL_SwapLE16(format->bitspersample);
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rogue_feel = (Uint8 *) format + sizeof(*format);
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if (sizeof(*format) == 16) {
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/* const Uint16 extra_info = ((rogue_feel[1] << 8) | rogue_feel[0]); */
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rogue_feel += sizeof(Uint16);
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}
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MS_ADPCM_state.wSamplesPerBlock = ((rogue_feel[1] << 8) | rogue_feel[0]);
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rogue_feel += sizeof(Uint16);
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MS_ADPCM_state.wNumCoef = ((rogue_feel[1] << 8) | rogue_feel[0]);
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rogue_feel += sizeof(Uint16);
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if (MS_ADPCM_state.wNumCoef != 7) {
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SDL_SetError("Unknown set of MS_ADPCM coefficients");
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return (-1);
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}
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for (i = 0; i < MS_ADPCM_state.wNumCoef; ++i) {
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MS_ADPCM_state.aCoeff[i][0] = ((rogue_feel[1] << 8) | rogue_feel[0]);
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rogue_feel += sizeof(Uint16);
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MS_ADPCM_state.aCoeff[i][1] = ((rogue_feel[1] << 8) | rogue_feel[0]);
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rogue_feel += sizeof(Uint16);
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}
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return (0);
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}
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static Sint32
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MS_ADPCM_nibble(struct MS_ADPCM_decodestate *state,
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Uint8 nybble, Sint16 * coeff)
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{
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const Sint32 max_audioval = ((1 << (16 - 1)) - 1);
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const Sint32 min_audioval = -(1 << (16 - 1));
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const Sint32 adaptive[] = {
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230, 230, 230, 230, 307, 409, 512, 614,
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768, 614, 512, 409, 307, 230, 230, 230
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};
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Sint32 new_sample, delta;
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new_sample = ((state->iSamp1 * coeff[0]) +
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(state->iSamp2 * coeff[1])) / 256;
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if (nybble & 0x08) {
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new_sample += state->iDelta * (nybble - 0x10);
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} else {
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new_sample += state->iDelta * nybble;
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}
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if (new_sample < min_audioval) {
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new_sample = min_audioval;
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} else if (new_sample > max_audioval) {
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new_sample = max_audioval;
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}
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delta = ((Sint32) state->iDelta * adaptive[nybble]) / 256;
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if (delta < 16) {
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delta = 16;
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}
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state->iDelta = (Uint16) delta;
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state->iSamp2 = state->iSamp1;
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state->iSamp1 = (Sint16) new_sample;
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return (new_sample);
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}
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static int
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MS_ADPCM_decode(Uint8 ** audio_buf, Uint32 * audio_len)
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{
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struct MS_ADPCM_decodestate *state[2];
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Uint8 *freeable, *encoded, *decoded;
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Sint32 encoded_len, samplesleft;
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Sint8 nybble;
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Uint8 stereo;
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Sint16 *coeff[2];
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Sint32 new_sample;
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/* Allocate the proper sized output buffer */
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encoded_len = *audio_len;
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encoded = *audio_buf;
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freeable = *audio_buf;
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*audio_len = (encoded_len / MS_ADPCM_state.wavefmt.blockalign) *
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MS_ADPCM_state.wSamplesPerBlock *
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MS_ADPCM_state.wavefmt.channels * sizeof(Sint16);
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*audio_buf = (Uint8 *) SDL_malloc(*audio_len);
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if (*audio_buf == NULL) {
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return SDL_OutOfMemory();
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}
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decoded = *audio_buf;
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/* Get ready... Go! */
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stereo = (MS_ADPCM_state.wavefmt.channels == 2);
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state[0] = &MS_ADPCM_state.state[0];
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state[1] = &MS_ADPCM_state.state[stereo];
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while (encoded_len >= MS_ADPCM_state.wavefmt.blockalign) {
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/* Grab the initial information for this block */
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state[0]->hPredictor = *encoded++;
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if (stereo) {
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state[1]->hPredictor = *encoded++;
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}
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state[0]->iDelta = ((encoded[1] << 8) | encoded[0]);
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encoded += sizeof(Sint16);
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if (stereo) {
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state[1]->iDelta = ((encoded[1] << 8) | encoded[0]);
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encoded += sizeof(Sint16);
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}
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state[0]->iSamp1 = ((encoded[1] << 8) | encoded[0]);
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encoded += sizeof(Sint16);
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if (stereo) {
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state[1]->iSamp1 = ((encoded[1] << 8) | encoded[0]);
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encoded += sizeof(Sint16);
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}
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state[0]->iSamp2 = ((encoded[1] << 8) | encoded[0]);
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encoded += sizeof(Sint16);
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if (stereo) {
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state[1]->iSamp2 = ((encoded[1] << 8) | encoded[0]);
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encoded += sizeof(Sint16);
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}
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coeff[0] = MS_ADPCM_state.aCoeff[state[0]->hPredictor];
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coeff[1] = MS_ADPCM_state.aCoeff[state[1]->hPredictor];
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/* Store the two initial samples we start with */
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decoded[0] = state[0]->iSamp2 & 0xFF;
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decoded[1] = state[0]->iSamp2 >> 8;
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decoded += 2;
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if (stereo) {
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decoded[0] = state[1]->iSamp2 & 0xFF;
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decoded[1] = state[1]->iSamp2 >> 8;
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decoded += 2;
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}
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decoded[0] = state[0]->iSamp1 & 0xFF;
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decoded[1] = state[0]->iSamp1 >> 8;
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decoded += 2;
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if (stereo) {
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decoded[0] = state[1]->iSamp1 & 0xFF;
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decoded[1] = state[1]->iSamp1 >> 8;
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decoded += 2;
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}
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/* Decode and store the other samples in this block */
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samplesleft = (MS_ADPCM_state.wSamplesPerBlock - 2) *
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MS_ADPCM_state.wavefmt.channels;
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while (samplesleft > 0) {
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nybble = (*encoded) >> 4;
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new_sample = MS_ADPCM_nibble(state[0], nybble, coeff[0]);
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decoded[0] = new_sample & 0xFF;
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new_sample >>= 8;
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decoded[1] = new_sample & 0xFF;
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decoded += 2;
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nybble = (*encoded) & 0x0F;
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new_sample = MS_ADPCM_nibble(state[1], nybble, coeff[1]);
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decoded[0] = new_sample & 0xFF;
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new_sample >>= 8;
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decoded[1] = new_sample & 0xFF;
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decoded += 2;
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++encoded;
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samplesleft -= 2;
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}
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encoded_len -= MS_ADPCM_state.wavefmt.blockalign;
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}
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SDL_free(freeable);
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return (0);
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}
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struct IMA_ADPCM_decodestate
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{
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Sint32 sample;
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Sint8 index;
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};
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static struct IMA_ADPCM_decoder
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{
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WaveFMT wavefmt;
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Uint16 wSamplesPerBlock;
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/* * * */
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struct IMA_ADPCM_decodestate state[2];
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} IMA_ADPCM_state;
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static int
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InitIMA_ADPCM(WaveFMT * format)
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{
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Uint8 *rogue_feel;
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/* Set the rogue pointer to the IMA_ADPCM specific data */
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IMA_ADPCM_state.wavefmt.encoding = SDL_SwapLE16(format->encoding);
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IMA_ADPCM_state.wavefmt.channels = SDL_SwapLE16(format->channels);
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IMA_ADPCM_state.wavefmt.frequency = SDL_SwapLE32(format->frequency);
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IMA_ADPCM_state.wavefmt.byterate = SDL_SwapLE32(format->byterate);
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IMA_ADPCM_state.wavefmt.blockalign = SDL_SwapLE16(format->blockalign);
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IMA_ADPCM_state.wavefmt.bitspersample =
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SDL_SwapLE16(format->bitspersample);
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rogue_feel = (Uint8 *) format + sizeof(*format);
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if (sizeof(*format) == 16) {
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/* const Uint16 extra_info = ((rogue_feel[1] << 8) | rogue_feel[0]); */
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rogue_feel += sizeof(Uint16);
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}
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IMA_ADPCM_state.wSamplesPerBlock = ((rogue_feel[1] << 8) | rogue_feel[0]);
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return (0);
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}
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static Sint32
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IMA_ADPCM_nibble(struct IMA_ADPCM_decodestate *state, Uint8 nybble)
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{
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const Sint32 max_audioval = ((1 << (16 - 1)) - 1);
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const Sint32 min_audioval = -(1 << (16 - 1));
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const int index_table[16] = {
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-1, -1, -1, -1,
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2, 4, 6, 8,
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-1, -1, -1, -1,
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2, 4, 6, 8
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};
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const Sint32 step_table[89] = {
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7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 21, 23, 25, 28, 31,
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34, 37, 41, 45, 50, 55, 60, 66, 73, 80, 88, 97, 107, 118, 130,
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143, 157, 173, 190, 209, 230, 253, 279, 307, 337, 371, 408,
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449, 494, 544, 598, 658, 724, 796, 876, 963, 1060, 1166, 1282,
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1411, 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, 3327,
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3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132, 7845, 8630,
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9493, 10442, 11487, 12635, 13899, 15289, 16818, 18500, 20350,
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22385, 24623, 27086, 29794, 32767
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};
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Sint32 delta, step;
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/* Compute difference and new sample value */
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if (state->index > 88) {
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state->index = 88;
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} else if (state->index < 0) {
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state->index = 0;
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}
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/* explicit cast to avoid gcc warning about using 'char' as array index */
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step = step_table[(int)state->index];
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delta = step >> 3;
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if (nybble & 0x04)
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delta += step;
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if (nybble & 0x02)
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delta += (step >> 1);
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if (nybble & 0x01)
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delta += (step >> 2);
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if (nybble & 0x08)
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delta = -delta;
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state->sample += delta;
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/* Update index value */
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state->index += index_table[nybble];
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/* Clamp output sample */
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if (state->sample > max_audioval) {
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state->sample = max_audioval;
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} else if (state->sample < min_audioval) {
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state->sample = min_audioval;
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}
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return (state->sample);
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}
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/* Fill the decode buffer with a channel block of data (8 samples) */
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static void
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Fill_IMA_ADPCM_block(Uint8 * decoded, Uint8 * encoded,
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int channel, int numchannels,
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struct IMA_ADPCM_decodestate *state)
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{
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int i;
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Sint8 nybble;
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Sint32 new_sample;
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decoded += (channel * 2);
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for (i = 0; i < 4; ++i) {
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nybble = (*encoded) & 0x0F;
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new_sample = IMA_ADPCM_nibble(state, nybble);
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decoded[0] = new_sample & 0xFF;
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new_sample >>= 8;
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decoded[1] = new_sample & 0xFF;
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decoded += 2 * numchannels;
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nybble = (*encoded) >> 4;
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new_sample = IMA_ADPCM_nibble(state, nybble);
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decoded[0] = new_sample & 0xFF;
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new_sample >>= 8;
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decoded[1] = new_sample & 0xFF;
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decoded += 2 * numchannels;
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++encoded;
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}
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}
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static int
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IMA_ADPCM_decode(Uint8 ** audio_buf, Uint32 * audio_len)
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{
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struct IMA_ADPCM_decodestate *state;
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Uint8 *freeable, *encoded, *decoded;
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Sint32 encoded_len, samplesleft;
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unsigned int c, channels;
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/* Check to make sure we have enough variables in the state array */
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channels = IMA_ADPCM_state.wavefmt.channels;
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if (channels > SDL_arraysize(IMA_ADPCM_state.state)) {
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SDL_SetError("IMA ADPCM decoder can only handle %u channels",
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(unsigned int)SDL_arraysize(IMA_ADPCM_state.state));
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return (-1);
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}
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state = IMA_ADPCM_state.state;
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/* Allocate the proper sized output buffer */
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encoded_len = *audio_len;
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encoded = *audio_buf;
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freeable = *audio_buf;
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*audio_len = (encoded_len / IMA_ADPCM_state.wavefmt.blockalign) *
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IMA_ADPCM_state.wSamplesPerBlock *
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IMA_ADPCM_state.wavefmt.channels * sizeof(Sint16);
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*audio_buf = (Uint8 *) SDL_malloc(*audio_len);
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if (*audio_buf == NULL) {
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return SDL_OutOfMemory();
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}
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decoded = *audio_buf;
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/* Get ready... Go! */
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while (encoded_len >= IMA_ADPCM_state.wavefmt.blockalign) {
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/* Grab the initial information for this block */
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for (c = 0; c < channels; ++c) {
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/* Fill the state information for this block */
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state[c].sample = ((encoded[1] << 8) | encoded[0]);
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encoded += 2;
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if (state[c].sample & 0x8000) {
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state[c].sample -= 0x10000;
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}
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state[c].index = *encoded++;
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/* Reserved byte in buffer header, should be 0 */
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if (*encoded++ != 0) {
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/* Uh oh, corrupt data? Buggy code? */ ;
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}
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/* Store the initial sample we start with */
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decoded[0] = (Uint8) (state[c].sample & 0xFF);
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decoded[1] = (Uint8) (state[c].sample >> 8);
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decoded += 2;
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}
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/* Decode and store the other samples in this block */
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samplesleft = (IMA_ADPCM_state.wSamplesPerBlock - 1) * channels;
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while (samplesleft > 0) {
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for (c = 0; c < channels; ++c) {
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Fill_IMA_ADPCM_block(decoded, encoded,
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c, channels, &state[c]);
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encoded += 4;
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samplesleft -= 8;
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}
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decoded += (channels * 8 * 2);
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}
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encoded_len -= IMA_ADPCM_state.wavefmt.blockalign;
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}
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SDL_free(freeable);
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return (0);
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}
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/* GUIDs that are used by WAVE_FORMAT_EXTENSIBLE */
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static const Uint8 extensible_pcm_guid[16] = { 1, 0, 0, 0, 0, 0, 16, 0, 128, 0, 0, 170, 0, 56, 155, 113 };
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static const Uint8 extensible_ieee_guid[16] = { 3, 0, 0, 0, 0, 0, 16, 0, 128, 0, 0, 170, 0, 56, 155, 113 };
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SDL_AudioSpec *
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SDL_LoadWAV_RW(SDL_RWops * src, int freesrc,
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SDL_AudioSpec * spec, Uint8 ** audio_buf, Uint32 * audio_len)
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{
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int was_error;
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Chunk chunk;
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int lenread;
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int IEEE_float_encoded, MS_ADPCM_encoded, IMA_ADPCM_encoded;
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int samplesize;
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/* WAV magic header */
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Uint32 RIFFchunk;
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Uint32 wavelen = 0;
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Uint32 WAVEmagic;
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Uint32 headerDiff = 0;
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/* FMT chunk */
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WaveFMT *format = NULL;
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WaveExtensibleFMT *ext = NULL;
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SDL_zero(chunk);
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/* Make sure we are passed a valid data source */
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was_error = 0;
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if (src == NULL) {
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was_error = 1;
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goto done;
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}
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/* Check the magic header */
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RIFFchunk = SDL_ReadLE32(src);
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wavelen = SDL_ReadLE32(src);
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if (wavelen == WAVE) { /* The RIFFchunk has already been read */
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WAVEmagic = wavelen;
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wavelen = RIFFchunk;
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RIFFchunk = RIFF;
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} else {
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WAVEmagic = SDL_ReadLE32(src);
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}
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if ((RIFFchunk != RIFF) || (WAVEmagic != WAVE)) {
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SDL_SetError("Unrecognized file type (not WAVE)");
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was_error = 1;
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goto done;
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}
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headerDiff += sizeof(Uint32); /* for WAVE */
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/* Read the audio data format chunk */
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chunk.data = NULL;
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do {
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SDL_free(chunk.data);
|
|
chunk.data = NULL;
|
|
lenread = ReadChunk(src, &chunk);
|
|
if (lenread < 0) {
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
/* 2 Uint32's for chunk header+len, plus the lenread */
|
|
headerDiff += lenread + 2 * sizeof(Uint32);
|
|
} while ((chunk.magic == FACT) || (chunk.magic == LIST) || (chunk.magic == BEXT) || (chunk.magic == JUNK));
|
|
|
|
/* Decode the audio data format */
|
|
format = (WaveFMT *) chunk.data;
|
|
if (chunk.magic != FMT) {
|
|
SDL_SetError("Complex WAVE files not supported");
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
IEEE_float_encoded = MS_ADPCM_encoded = IMA_ADPCM_encoded = 0;
|
|
switch (SDL_SwapLE16(format->encoding)) {
|
|
case PCM_CODE:
|
|
/* We can understand this */
|
|
break;
|
|
case IEEE_FLOAT_CODE:
|
|
IEEE_float_encoded = 1;
|
|
/* We can understand this */
|
|
break;
|
|
case MS_ADPCM_CODE:
|
|
/* Try to understand this */
|
|
if (InitMS_ADPCM(format) < 0) {
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
MS_ADPCM_encoded = 1;
|
|
break;
|
|
case IMA_ADPCM_CODE:
|
|
/* Try to understand this */
|
|
if (InitIMA_ADPCM(format) < 0) {
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
IMA_ADPCM_encoded = 1;
|
|
break;
|
|
case EXTENSIBLE_CODE:
|
|
/* note that this ignores channel masks, smaller valid bit counts
|
|
inside a larger container, and most subtypes. This is just enough
|
|
to get things that didn't really _need_ WAVE_FORMAT_EXTENSIBLE
|
|
to be useful working when they use this format flag. */
|
|
ext = (WaveExtensibleFMT *) format;
|
|
if (SDL_SwapLE16(ext->size) < 22) {
|
|
SDL_SetError("bogus extended .wav header");
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
if (SDL_memcmp(ext->subformat, extensible_pcm_guid, 16) == 0) {
|
|
break; /* cool. */
|
|
} else if (SDL_memcmp(ext->subformat, extensible_ieee_guid, 16) == 0) {
|
|
IEEE_float_encoded = 1;
|
|
break;
|
|
}
|
|
break;
|
|
case MP3_CODE:
|
|
SDL_SetError("MPEG Layer 3 data not supported");
|
|
was_error = 1;
|
|
goto done;
|
|
default:
|
|
SDL_SetError("Unknown WAVE data format: 0x%.4x",
|
|
SDL_SwapLE16(format->encoding));
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
SDL_zerop(spec);
|
|
spec->freq = SDL_SwapLE32(format->frequency);
|
|
|
|
if (IEEE_float_encoded) {
|
|
if ((SDL_SwapLE16(format->bitspersample)) != 32) {
|
|
was_error = 1;
|
|
} else {
|
|
spec->format = AUDIO_F32;
|
|
}
|
|
} else {
|
|
switch (SDL_SwapLE16(format->bitspersample)) {
|
|
case 4:
|
|
if (MS_ADPCM_encoded || IMA_ADPCM_encoded) {
|
|
spec->format = AUDIO_S16;
|
|
} else {
|
|
was_error = 1;
|
|
}
|
|
break;
|
|
case 8:
|
|
spec->format = AUDIO_U8;
|
|
break;
|
|
case 16:
|
|
spec->format = AUDIO_S16;
|
|
break;
|
|
case 32:
|
|
spec->format = AUDIO_S32;
|
|
break;
|
|
default:
|
|
was_error = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (was_error) {
|
|
SDL_SetError("Unknown %d-bit PCM data format",
|
|
SDL_SwapLE16(format->bitspersample));
|
|
goto done;
|
|
}
|
|
spec->channels = (Uint8) SDL_SwapLE16(format->channels);
|
|
spec->samples = 4096; /* Good default buffer size */
|
|
|
|
/* Read the audio data chunk */
|
|
*audio_buf = NULL;
|
|
do {
|
|
SDL_free(*audio_buf);
|
|
*audio_buf = NULL;
|
|
lenread = ReadChunk(src, &chunk);
|
|
if (lenread < 0) {
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
*audio_len = lenread;
|
|
*audio_buf = chunk.data;
|
|
if (chunk.magic != DATA)
|
|
headerDiff += lenread + 2 * sizeof(Uint32);
|
|
} while (chunk.magic != DATA);
|
|
headerDiff += 2 * sizeof(Uint32); /* for the data chunk and len */
|
|
|
|
if (MS_ADPCM_encoded) {
|
|
if (MS_ADPCM_decode(audio_buf, audio_len) < 0) {
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
}
|
|
if (IMA_ADPCM_encoded) {
|
|
if (IMA_ADPCM_decode(audio_buf, audio_len) < 0) {
|
|
was_error = 1;
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
/* Don't return a buffer that isn't a multiple of samplesize */
|
|
samplesize = ((SDL_AUDIO_BITSIZE(spec->format)) / 8) * spec->channels;
|
|
*audio_len &= ~(samplesize - 1);
|
|
|
|
done:
|
|
SDL_free(format);
|
|
if (src) {
|
|
if (freesrc) {
|
|
SDL_RWclose(src);
|
|
} else {
|
|
/* seek to the end of the file (given by the RIFF chunk) */
|
|
SDL_RWseek(src, wavelen - chunk.length - headerDiff, RW_SEEK_CUR);
|
|
}
|
|
}
|
|
if (was_error) {
|
|
spec = NULL;
|
|
}
|
|
return (spec);
|
|
}
|
|
|
|
/* Since the WAV memory is allocated in the shared library, it must also
|
|
be freed here. (Necessary under Win32, VC++)
|
|
*/
|
|
void
|
|
SDL_FreeWAV(Uint8 * audio_buf)
|
|
{
|
|
SDL_free(audio_buf);
|
|
}
|
|
|
|
static int
|
|
ReadChunk(SDL_RWops * src, Chunk * chunk)
|
|
{
|
|
chunk->magic = SDL_ReadLE32(src);
|
|
chunk->length = SDL_ReadLE32(src);
|
|
chunk->data = (Uint8 *) SDL_malloc(chunk->length);
|
|
if (chunk->data == NULL) {
|
|
return SDL_OutOfMemory();
|
|
}
|
|
if (SDL_RWread(src, chunk->data, chunk->length, 1) != 1) {
|
|
SDL_free(chunk->data);
|
|
chunk->data = NULL;
|
|
return SDL_Error(SDL_EFREAD);
|
|
}
|
|
return (chunk->length);
|
|
}
|
|
|
|
/* vi: set ts=4 sw=4 expandtab: */
|