292e4e90d7
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7660 a1c6a512-1295-4272-9138-f99709370657
1048 lines
33 KiB
C
1048 lines
33 KiB
C
/*
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* ALAC (Apple Lossless Audio Codec) decoder
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* Copyright (c) 2005 David Hammerton
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* All rights reserved.
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*
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* This is the actual decoder.
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*
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* http://crazney.net/programs/itunes/alac.html
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*
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* Permission is hereby granted, free of charge, to any person
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* obtaining a copy of this software and associated documentation
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* files (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use,
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* copy, modify, merge, publish, distribute, sublicense, and/or
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* sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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* OTHER DEALINGS IN THE SOFTWARE.
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*
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <inttypes.h>
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#include "../codec.h"
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#include "decomp.h"
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#define _Swap32(v) do { \
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v = (((v) & 0x000000FF) << 0x18) | \
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(((v) & 0x0000FF00) << 0x08) | \
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(((v) & 0x00FF0000) >> 0x08) | \
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(((v) & 0xFF000000) >> 0x18); } while(0)
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#define _Swap16(v) do { \
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v = (((v) & 0x00FF) << 0x08) | \
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(((v) & 0xFF00) >> 0x08); } while (0)
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int16_t predictor_coef_table[32] IBSS_ATTR;
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int16_t predictor_coef_table_a[32] IBSS_ATTR;
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int16_t predictor_coef_table_b[32] IBSS_ATTR;
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int32_t predicterror_buffer_a[4096];
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int32_t predicterror_buffer_b[4096];
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int32_t outputsamples_buffer_a[4096] IBSS_ATTR;
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int32_t outputsamples_buffer_b[4096] IBSS_ATTR;
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void alac_set_info(alac_file *alac, char *inputbuffer)
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{
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char *ptr = inputbuffer;
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ptr += 4; /* size */
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ptr += 4; /* frma */
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ptr += 4; /* alac */
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ptr += 4; /* size */
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ptr += 4; /* alac */
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ptr += 4; /* 0 ? */
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alac->setinfo_max_samples_per_frame = *(uint32_t*)ptr; /* buffer size / 2 ? */
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#ifdef ROCKBOX_LITTLE_ENDIAN
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_Swap32(alac->setinfo_max_samples_per_frame);
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#endif
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ptr += 4;
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alac->setinfo_7a = *(uint8_t*)ptr;
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ptr += 1;
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alac->setinfo_sample_size = *(uint8_t*)ptr;
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ptr += 1;
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alac->setinfo_rice_historymult = *(uint8_t*)ptr;
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ptr += 1;
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alac->setinfo_rice_initialhistory = *(uint8_t*)ptr;
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ptr += 1;
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alac->setinfo_rice_kmodifier = *(uint8_t*)ptr;
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ptr += 1;
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alac->setinfo_7f = *(uint8_t*)ptr;
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ptr += 1;
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alac->setinfo_80 = *(uint16_t*)ptr;
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#ifdef ROCKBOX_LITTLE_ENDIAN
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_Swap16(alac->setinfo_80);
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#endif
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ptr += 2;
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alac->setinfo_82 = *(uint32_t*)ptr;
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#ifdef ROCKBOX_LITTLE_ENDIAN
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_Swap32(alac->setinfo_82);
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#endif
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ptr += 4;
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alac->setinfo_86 = *(uint32_t*)ptr;
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#ifdef ROCKBOX_LITTLE_ENDIAN
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_Swap32(alac->setinfo_86);
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#endif
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ptr += 4;
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alac->setinfo_8a_rate = *(uint32_t*)ptr;
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#ifdef ROCKBOX_LITTLE_ENDIAN
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_Swap32(alac->setinfo_8a_rate);
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#endif
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ptr += 4;
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}
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/* stream reading */
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/* supports reading 1 to 16 bits, in big endian format */
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static uint32_t readbits_16(alac_file *alac, int bits)
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{
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uint32_t result;
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int new_accumulator;
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result = (alac->input_buffer[0] << 16) |
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(alac->input_buffer[1] << 8) |
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(alac->input_buffer[2]);
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/* shift left by the number of bits we've already read,
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* so that the top 'n' bits of the 24 bits we read will
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* be the return bits */
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result = result << alac->input_buffer_bitaccumulator;
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result = result & 0x00ffffff;
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/* and then only want the top 'n' bits from that, where
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* n is 'bits' */
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result = result >> (24 - bits);
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new_accumulator = (alac->input_buffer_bitaccumulator + bits);
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/* increase the buffer pointer if we've read over n bytes. */
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alac->input_buffer += (new_accumulator >> 3);
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/* and the remainder goes back into the bit accumulator */
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alac->input_buffer_bitaccumulator = (new_accumulator & 7);
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return result;
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}
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/* supports reading 1 to 32 bits, in big endian format */
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static uint32_t readbits(alac_file *alac, int bits)
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{
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int32_t result = 0;
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if (bits > 16)
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{
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bits -= 16;
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result = readbits_16(alac, 16) << bits;
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}
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result |= readbits_16(alac, bits);
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return result;
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}
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/* reads a single bit */
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static int readbit(alac_file *alac)
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{
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int result;
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int new_accumulator;
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result = alac->input_buffer[0];
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result = result << alac->input_buffer_bitaccumulator;
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result = result >> 7 & 1;
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new_accumulator = (alac->input_buffer_bitaccumulator + 1);
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alac->input_buffer += (new_accumulator / 8);
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alac->input_buffer_bitaccumulator = (new_accumulator % 8);
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return result;
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}
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static void unreadbits(alac_file *alac, int bits)
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{
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int new_accumulator = (alac->input_buffer_bitaccumulator - bits);
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alac->input_buffer += (new_accumulator >> 3);
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alac->input_buffer_bitaccumulator = (new_accumulator & 7);
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if (alac->input_buffer_bitaccumulator < 0)
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alac->input_buffer_bitaccumulator *= -1;
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}
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/* hideously inefficient. could use a bitmask search,
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* alternatively bsr on x86,
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*/
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static int count_leading_zeros(int32_t input)
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{
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int i = 0;
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while (!(0x80000000 & input) && i < 32)
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{
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i++;
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input = input << 1;
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}
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return i;
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}
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void basterdised_rice_decompress(alac_file *alac,
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int32_t *output_buffer,
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int output_size,
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int readsamplesize, /* arg_10 */
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int rice_initialhistory, /* arg424->b */
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int rice_kmodifier, /* arg424->d */
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int rice_historymult, /* arg424->c */
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int rice_kmodifier_mask /* arg424->e */
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)
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{
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int output_count;
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unsigned int history = rice_initialhistory;
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int sign_modifier = 0;
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for (output_count = 0; output_count < output_size; output_count++)
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{
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int32_t x = 0;
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int32_t x_modified;
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int32_t final_val;
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/* read x - number of 1s before 0 represent the rice */
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while (x <= 8 && readbit(alac))
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{
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x++;
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}
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if (x > 8) /* RICE THRESHOLD */
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{ /* use alternative encoding */
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int32_t value;
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value = readbits(alac, readsamplesize);
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/* mask value to readsamplesize size */
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if (readsamplesize != 32)
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value &= (0xffffffff >> (32 - readsamplesize));
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x = value;
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}
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else
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{ /* standard rice encoding */
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int extrabits;
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int k; /* size of extra bits */
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/* read k, that is bits as is */
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k = 31 - rice_kmodifier - count_leading_zeros((history >> 9) + 3);
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if (k < 0) k += rice_kmodifier;
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else k = rice_kmodifier;
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if (k != 1)
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{
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extrabits = readbits(alac, k);
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/* multiply x by 2^k - 1, as part of their strange algorithm */
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x = (x << k) - x;
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if (extrabits > 1)
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{
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x += extrabits - 1;
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}
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else unreadbits(alac, 1);
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}
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}
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x_modified = sign_modifier + x;
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final_val = (x_modified + 1) / 2;
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if (x_modified & 1) final_val *= -1;
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output_buffer[output_count] = final_val;
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sign_modifier = 0;
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/* now update the history */
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history += (x_modified * rice_historymult)
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- ((history * rice_historymult) >> 9);
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if (x_modified > 0xffff)
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history = 0xffff;
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/* special case: there may be compressed blocks of 0 */
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if ((history < 128) && (output_count+1 < output_size))
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{
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int block_size;
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sign_modifier = 1;
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x = 0;
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while (x <= 8 && readbit(alac))
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{
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x++;
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}
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if (x > 8)
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{
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block_size = readbits(alac, 16);
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block_size &= 0xffff;
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}
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else
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{
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int k;
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int extrabits;
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k = count_leading_zeros(history) + ((history + 16) >> 6 /* / 64 */) - 24;
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extrabits = readbits(alac, k);
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block_size = (((1 << k) - 1) & rice_kmodifier_mask) * x
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+ extrabits - 1;
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if (extrabits < 2)
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{
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x = 1 - extrabits;
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block_size += x;
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unreadbits(alac, 1);
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}
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}
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if (block_size > 0)
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{
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memset(&output_buffer[output_count+1], 0, block_size * 4);
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output_count += block_size;
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}
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if (block_size > 0xffff)
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sign_modifier = 0;
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history = 0;
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}
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}
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}
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#define SIGN_EXTENDED32(val, bits) ((val << (32 - bits)) >> (32 - bits))
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#define SIGN_ONLY(v) \
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((v < 0) ? (-1) : \
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((v > 0) ? (1) : \
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(0)))
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static void predictor_decompress_fir_adapt(int32_t *error_buffer,
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int32_t *buffer_out,
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int output_size,
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int readsamplesize,
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int16_t *predictor_coef_table,
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int predictor_coef_num,
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int predictor_quantitization)
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{
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int i;
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/* first sample always copies */
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*buffer_out = *error_buffer;
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if (!predictor_coef_num)
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{
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if (output_size <= 1) return;
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memcpy(buffer_out+1, error_buffer+1, (output_size-1) * 4);
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return;
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}
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if (predictor_coef_num == 0x1f) /* 11111 - max value of predictor_coef_num */
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{ /* second-best case scenario for fir decompression,
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* error describes a small difference from the previous sample only
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*/
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if (output_size <= 1) return;
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for (i = 0; i < output_size - 1; i++)
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{
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int32_t prev_value;
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int32_t error_value;
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prev_value = buffer_out[i];
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error_value = error_buffer[i+1];
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buffer_out[i+1] = SIGN_EXTENDED32((prev_value + error_value), readsamplesize);
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}
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return;
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}
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/* read warm-up samples */
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if (predictor_coef_num > 0)
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{
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int i;
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for (i = 0; i < predictor_coef_num; i++)
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{
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int32_t val;
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val = buffer_out[i] + error_buffer[i+1];
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val = SIGN_EXTENDED32(val, readsamplesize);
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buffer_out[i+1] = val;
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}
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}
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/* 4 and 8 are very common cases (the only ones i've seen).
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The following code is an initial attempt to unroll and optimise
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these two cases by the Rockbox project. More work is needed.
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*/
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/* optimised case: 4 */
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if (predictor_coef_num == 4)
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{
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for (i = 4 + 1; i < output_size; i++)
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{
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int sum = 0;
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int outval;
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int error_val = error_buffer[i];
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sum = (buffer_out[4] - buffer_out[0]) * predictor_coef_table[0]
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+ (buffer_out[3] - buffer_out[0]) * predictor_coef_table[1]
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+ (buffer_out[2] - buffer_out[0]) * predictor_coef_table[2]
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+ (buffer_out[1] - buffer_out[0]) * predictor_coef_table[3];
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outval = (1 << (predictor_quantitization-1)) + sum;
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outval = outval >> predictor_quantitization;
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outval = outval + buffer_out[0] + error_val;
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outval = SIGN_EXTENDED32(outval, readsamplesize);
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buffer_out[4+1] = outval;
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if (error_val > 0)
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{
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int predictor_num = 4 - 1;
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while (predictor_num >= 0 && error_val > 0)
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{
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int val = buffer_out[0] - buffer_out[4 - predictor_num];
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if (val!=0) {
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if (val < 0) {
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predictor_coef_table[predictor_num]++;
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val=-val;
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} else {
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predictor_coef_table[predictor_num]--;;
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}
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error_val -= ((val >> predictor_quantitization) * (4 - predictor_num));
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}
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predictor_num--;
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}
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}
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else if (error_val < 0)
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{
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int predictor_num = 4 - 1;
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while (predictor_num >= 0 && error_val < 0)
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{
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int val = buffer_out[0] - buffer_out[4 - predictor_num];
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if (val != 0) {
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if (val > 0) {
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predictor_coef_table[predictor_num]++;
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val=-val; /* neg value */
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} else {
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predictor_coef_table[predictor_num]--;
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}
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error_val -= ((val >> predictor_quantitization) * (4 - predictor_num));
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}
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predictor_num--;
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}
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}
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buffer_out++;
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}
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return;
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}
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/* optimised case: 8 */
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if (predictor_coef_num == 8)
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{
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for (i = 8 + 1;
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i < output_size;
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i++)
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{
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int sum;
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int outval;
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int error_val = error_buffer[i];
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sum = (buffer_out[8] - buffer_out[0]) * predictor_coef_table[0]
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+ (buffer_out[7] - buffer_out[0]) * predictor_coef_table[1]
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+ (buffer_out[6] - buffer_out[0]) * predictor_coef_table[2]
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+ (buffer_out[5] - buffer_out[0]) * predictor_coef_table[3]
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+ (buffer_out[4] - buffer_out[0]) * predictor_coef_table[4]
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+ (buffer_out[3] - buffer_out[0]) * predictor_coef_table[5]
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+ (buffer_out[2] - buffer_out[0]) * predictor_coef_table[6]
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+ (buffer_out[1] - buffer_out[0]) * predictor_coef_table[7];
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outval = (1 << (predictor_quantitization-1)) + sum;
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outval = outval >> predictor_quantitization;
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outval = outval + buffer_out[0] + error_val;
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outval = SIGN_EXTENDED32(outval, readsamplesize);
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buffer_out[8+1] = outval;
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if (error_val > 0)
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{
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int predictor_num = 8 - 1;
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while (predictor_num >= 0 && error_val > 0)
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{
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int val = buffer_out[0] - buffer_out[8 - predictor_num];
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if (val!=0) {
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if (val < 0) {
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predictor_coef_table[predictor_num]++;
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val=-val;
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} else {
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predictor_coef_table[predictor_num]--;;
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}
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error_val -= ((val >> predictor_quantitization) * (8 - predictor_num));
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}
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predictor_num--;
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}
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}
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else if (error_val < 0)
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{
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int predictor_num = 8 - 1;
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while (predictor_num >= 0 && error_val < 0)
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{
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int val = buffer_out[0] - buffer_out[8 - predictor_num];
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if (val != 0) {
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if (val > 0) {
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predictor_coef_table[predictor_num]++;
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val=-val; /* neg value */
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} else {
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predictor_coef_table[predictor_num]--;
|
|
}
|
|
error_val -= ((val >> predictor_quantitization) * (8 - predictor_num));
|
|
}
|
|
predictor_num--;
|
|
}
|
|
}
|
|
|
|
buffer_out++;
|
|
}
|
|
return;
|
|
}
|
|
|
|
/* general case */
|
|
if (predictor_coef_num > 0)
|
|
{
|
|
for (i = predictor_coef_num + 1;
|
|
i < output_size;
|
|
i++)
|
|
{
|
|
int j;
|
|
int sum = 0;
|
|
int outval;
|
|
int error_val = error_buffer[i];
|
|
|
|
for (j = 0; j < predictor_coef_num; j++)
|
|
{
|
|
sum += (buffer_out[predictor_coef_num-j] - buffer_out[0]) *
|
|
predictor_coef_table[j];
|
|
}
|
|
|
|
outval = (1 << (predictor_quantitization-1)) + sum;
|
|
outval = outval >> predictor_quantitization;
|
|
outval = outval + buffer_out[0] + error_val;
|
|
outval = SIGN_EXTENDED32(outval, readsamplesize);
|
|
|
|
buffer_out[predictor_coef_num+1] = outval;
|
|
|
|
if (error_val > 0)
|
|
{
|
|
int predictor_num = predictor_coef_num - 1;
|
|
|
|
while (predictor_num >= 0 && error_val > 0)
|
|
{
|
|
int val = buffer_out[0] - buffer_out[predictor_coef_num - predictor_num];
|
|
int sign = SIGN_ONLY(val);
|
|
|
|
predictor_coef_table[predictor_num] -= sign;
|
|
|
|
val *= sign; /* absolute value */
|
|
|
|
error_val -= ((val >> predictor_quantitization) *
|
|
(predictor_coef_num - predictor_num));
|
|
|
|
predictor_num--;
|
|
}
|
|
}
|
|
else if (error_val < 0)
|
|
{
|
|
int predictor_num = predictor_coef_num - 1;
|
|
|
|
while (predictor_num >= 0 && error_val < 0)
|
|
{
|
|
int val = buffer_out[0] - buffer_out[predictor_coef_num - predictor_num];
|
|
int sign = - SIGN_ONLY(val);
|
|
|
|
predictor_coef_table[predictor_num] -= sign;
|
|
|
|
val *= sign; /* neg value */
|
|
|
|
error_val -= ((val >> predictor_quantitization) *
|
|
(predictor_coef_num - predictor_num));
|
|
|
|
predictor_num--;
|
|
}
|
|
}
|
|
|
|
buffer_out++;
|
|
}
|
|
}
|
|
}
|
|
|
|
void deinterlace_16(int32_t *buffer_a, int32_t *buffer_b,
|
|
int16_t *buffer_out,
|
|
int numchannels, int numsamples,
|
|
uint8_t interlacing_shift,
|
|
uint8_t interlacing_leftweight)
|
|
{
|
|
int i;
|
|
if (numsamples <= 0) return;
|
|
|
|
/* weighted interlacing */
|
|
if (interlacing_leftweight)
|
|
{
|
|
for (i = 0; i < numsamples; i++)
|
|
{
|
|
int32_t difference, midright;
|
|
|
|
midright = buffer_a[i];
|
|
difference = buffer_b[i];
|
|
|
|
buffer_out[i*numchannels] = (midright - ((difference * interlacing_leftweight) >> interlacing_shift)) + difference;
|
|
buffer_out[i*numchannels + 1] = midright - ((difference * interlacing_leftweight) >> interlacing_shift);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
/* otherwise basic interlacing took place */
|
|
for (i = 0; i < numsamples; i++)
|
|
{
|
|
buffer_out[i*numchannels] = buffer_a[i];
|
|
buffer_out[i*numchannels + 1] = buffer_b[i];
|
|
}
|
|
}
|
|
|
|
int16_t* decode_frame(alac_file *alac,
|
|
unsigned char *inbuffer,
|
|
int *outputsize,
|
|
void (*yield)(void))
|
|
{
|
|
int channels;
|
|
int16_t* outbuffer;
|
|
int32_t outputsamples = alac->setinfo_max_samples_per_frame;
|
|
|
|
/* setup the stream */
|
|
alac->input_buffer = inbuffer;
|
|
alac->input_buffer_bitaccumulator = 0;
|
|
|
|
/* We can share the same buffer for outputbuffer
|
|
and outputsamples_buffer_b - and hence have them both in IRAM*/
|
|
outbuffer=(int16_t*)outputsamples_buffer_b;
|
|
|
|
channels = readbits(alac, 3);
|
|
|
|
*outputsize = outputsamples * alac->bytespersample;
|
|
|
|
switch(channels)
|
|
{
|
|
case 0: /* 1 channel */
|
|
{
|
|
int hassize;
|
|
int isnotcompressed;
|
|
int readsamplesize;
|
|
|
|
int wasted_bytes;
|
|
int ricemodifier;
|
|
|
|
|
|
/* 2^result = something to do with output waiting.
|
|
* perhaps matters if we read > 1 frame in a pass?
|
|
*/
|
|
readbits(alac, 4);
|
|
|
|
readbits(alac, 12); /* unknown, skip 12 bits */
|
|
|
|
hassize = readbits(alac, 1); /* the output sample size is stored soon */
|
|
|
|
wasted_bytes = readbits(alac, 2); /* unknown ? */
|
|
|
|
isnotcompressed = readbits(alac, 1); /* whether the frame is compressed */
|
|
|
|
if (hassize)
|
|
{
|
|
/* now read the number of samples,
|
|
* as a 32bit integer */
|
|
outputsamples = readbits(alac, 32);
|
|
*outputsize = outputsamples * alac->bytespersample;
|
|
}
|
|
|
|
readsamplesize = alac->setinfo_sample_size - (wasted_bytes * 8);
|
|
|
|
if (!isnotcompressed)
|
|
{ /* so it is compressed */
|
|
int predictor_coef_num;
|
|
int prediction_type;
|
|
int prediction_quantitization;
|
|
int i;
|
|
|
|
/* skip 16 bits, not sure what they are. seem to be used in
|
|
* two channel case */
|
|
readbits(alac, 8);
|
|
readbits(alac, 8);
|
|
|
|
prediction_type = readbits(alac, 4);
|
|
prediction_quantitization = readbits(alac, 4);
|
|
|
|
ricemodifier = readbits(alac, 3);
|
|
predictor_coef_num = readbits(alac, 5);
|
|
|
|
/* read the predictor table */
|
|
for (i = 0; i < predictor_coef_num; i++)
|
|
{
|
|
predictor_coef_table[i] = (int16_t)readbits(alac, 16);
|
|
}
|
|
|
|
if (wasted_bytes)
|
|
{
|
|
/* these bytes seem to have something to do with
|
|
* > 2 channel files.
|
|
*/
|
|
//fprintf(stderr, "FIXME: unimplemented, unhandling of wasted_bytes\n");
|
|
}
|
|
|
|
yield();
|
|
|
|
basterdised_rice_decompress(alac,
|
|
predicterror_buffer_a,
|
|
outputsamples,
|
|
readsamplesize,
|
|
alac->setinfo_rice_initialhistory,
|
|
alac->setinfo_rice_kmodifier,
|
|
ricemodifier * alac->setinfo_rice_historymult / 4,
|
|
(1 << alac->setinfo_rice_kmodifier) - 1);
|
|
|
|
yield();
|
|
|
|
if (prediction_type == 0)
|
|
{ /* adaptive fir */
|
|
predictor_decompress_fir_adapt(predicterror_buffer_a,
|
|
outputsamples_buffer_a,
|
|
outputsamples,
|
|
readsamplesize,
|
|
predictor_coef_table,
|
|
predictor_coef_num,
|
|
prediction_quantitization);
|
|
}
|
|
else
|
|
{
|
|
//fprintf(stderr, "FIXME: unhandled predicition type: %i\n", prediction_type);
|
|
/* i think the only other prediction type (or perhaps this is just a
|
|
* boolean?) runs adaptive fir twice.. like:
|
|
* predictor_decompress_fir_adapt(predictor_error, tempout, ...)
|
|
* predictor_decompress_fir_adapt(predictor_error, outputsamples ...)
|
|
* little strange..
|
|
*/
|
|
}
|
|
|
|
}
|
|
else
|
|
{ /* not compressed, easy case */
|
|
if (readsamplesize <= 16)
|
|
{
|
|
int i;
|
|
for (i = 0; i < outputsamples; i++)
|
|
{
|
|
int32_t audiobits = readbits(alac, readsamplesize);
|
|
|
|
audiobits = SIGN_EXTENDED32(audiobits, readsamplesize);
|
|
|
|
outputsamples_buffer_a[i] = audiobits;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
int i;
|
|
for (i = 0; i < outputsamples; i++)
|
|
{
|
|
int32_t audiobits;
|
|
|
|
audiobits = readbits(alac, 16);
|
|
/* special case of sign extension..
|
|
* as we'll be ORing the low 16bits into this */
|
|
audiobits = audiobits << 16;
|
|
audiobits = audiobits >> (32 - readsamplesize);
|
|
|
|
audiobits |= readbits(alac, readsamplesize - 16);
|
|
|
|
outputsamples_buffer_a[i] = audiobits;
|
|
}
|
|
}
|
|
/* wasted_bytes = 0; // unused */
|
|
}
|
|
|
|
yield();
|
|
|
|
switch(alac->setinfo_sample_size)
|
|
{
|
|
case 16:
|
|
{
|
|
int i;
|
|
for (i = 0; i < outputsamples; i++)
|
|
{
|
|
/* Output mono data as stereo */
|
|
outbuffer[i*2] = outputsamples_buffer_a[i];
|
|
outbuffer[i*2+1] = outputsamples_buffer_a[i];
|
|
}
|
|
break;
|
|
}
|
|
case 20:
|
|
case 24:
|
|
case 32:
|
|
//fprintf(stderr, "FIXME: unimplemented sample size %i\n", alac->setinfo_sample_size);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
case 1: /* 2 channels */
|
|
{
|
|
int hassize;
|
|
int isnotcompressed;
|
|
int readsamplesize;
|
|
|
|
int wasted_bytes;
|
|
|
|
uint8_t interlacing_shift;
|
|
uint8_t interlacing_leftweight;
|
|
|
|
/* 2^result = something to do with output waiting.
|
|
* perhaps matters if we read > 1 frame in a pass?
|
|
*/
|
|
readbits(alac, 4);
|
|
|
|
readbits(alac, 12); /* unknown, skip 12 bits */
|
|
|
|
hassize = readbits(alac, 1); /* the output sample size is stored soon */
|
|
|
|
wasted_bytes = readbits(alac, 2); /* unknown ? */
|
|
|
|
isnotcompressed = readbits(alac, 1); /* whether the frame is compressed */
|
|
|
|
if (hassize)
|
|
{
|
|
/* now read the number of samples,
|
|
* as a 32bit integer */
|
|
outputsamples = readbits(alac, 32);
|
|
*outputsize = outputsamples * alac->bytespersample;
|
|
}
|
|
|
|
readsamplesize = alac->setinfo_sample_size - (wasted_bytes * 8) + 1;
|
|
|
|
yield();
|
|
if (!isnotcompressed)
|
|
{ /* compressed */
|
|
int predictor_coef_num_a;
|
|
int prediction_type_a;
|
|
int prediction_quantitization_a;
|
|
int ricemodifier_a;
|
|
|
|
int predictor_coef_num_b;
|
|
int prediction_type_b;
|
|
int prediction_quantitization_b;
|
|
int ricemodifier_b;
|
|
|
|
int i;
|
|
|
|
interlacing_shift = readbits(alac, 8);
|
|
interlacing_leftweight = readbits(alac, 8);
|
|
|
|
/******** channel 1 ***********/
|
|
prediction_type_a = readbits(alac, 4);
|
|
prediction_quantitization_a = readbits(alac, 4);
|
|
|
|
ricemodifier_a = readbits(alac, 3);
|
|
predictor_coef_num_a = readbits(alac, 5);
|
|
|
|
/* read the predictor table */
|
|
for (i = 0; i < predictor_coef_num_a; i++)
|
|
{
|
|
predictor_coef_table_a[i] = (int16_t)readbits(alac, 16);
|
|
}
|
|
|
|
/******** channel 2 *********/
|
|
prediction_type_b = readbits(alac, 4);
|
|
prediction_quantitization_b = readbits(alac, 4);
|
|
|
|
ricemodifier_b = readbits(alac, 3);
|
|
predictor_coef_num_b = readbits(alac, 5);
|
|
|
|
/* read the predictor table */
|
|
for (i = 0; i < predictor_coef_num_b; i++)
|
|
{
|
|
predictor_coef_table_b[i] = (int16_t)readbits(alac, 16);
|
|
}
|
|
|
|
/*********************/
|
|
if (wasted_bytes)
|
|
{ /* see mono case */
|
|
//fprintf(stderr, "FIXME: unimplemented, unhandling of wasted_bytes\n");
|
|
}
|
|
|
|
yield();
|
|
/* channel 1 */
|
|
basterdised_rice_decompress(alac,
|
|
predicterror_buffer_a,
|
|
outputsamples,
|
|
readsamplesize,
|
|
alac->setinfo_rice_initialhistory,
|
|
alac->setinfo_rice_kmodifier,
|
|
ricemodifier_a * alac->setinfo_rice_historymult / 4,
|
|
(1 << alac->setinfo_rice_kmodifier) - 1);
|
|
|
|
yield();
|
|
if (prediction_type_a == 0)
|
|
{ /* adaptive fir */
|
|
predictor_decompress_fir_adapt(predicterror_buffer_a,
|
|
outputsamples_buffer_a,
|
|
outputsamples,
|
|
readsamplesize,
|
|
predictor_coef_table_a,
|
|
predictor_coef_num_a,
|
|
prediction_quantitization_a);
|
|
}
|
|
else
|
|
{ /* see mono case */
|
|
//fprintf(stderr, "FIXME: unhandled predicition type: %i\n", prediction_type_a);
|
|
}
|
|
|
|
yield();
|
|
|
|
/* channel 2 */
|
|
basterdised_rice_decompress(alac,
|
|
predicterror_buffer_b,
|
|
outputsamples,
|
|
readsamplesize,
|
|
alac->setinfo_rice_initialhistory,
|
|
alac->setinfo_rice_kmodifier,
|
|
ricemodifier_b * alac->setinfo_rice_historymult / 4,
|
|
(1 << alac->setinfo_rice_kmodifier) - 1);
|
|
|
|
yield();
|
|
if (prediction_type_b == 0)
|
|
{ /* adaptive fir */
|
|
predictor_decompress_fir_adapt(predicterror_buffer_b,
|
|
outputsamples_buffer_b,
|
|
outputsamples,
|
|
readsamplesize,
|
|
predictor_coef_table_b,
|
|
predictor_coef_num_b,
|
|
prediction_quantitization_b);
|
|
}
|
|
else
|
|
{
|
|
//fprintf(stderr, "FIXME: unhandled predicition type: %i\n", prediction_type_b);
|
|
}
|
|
}
|
|
else
|
|
{ /* not compressed, easy case */
|
|
if (alac->setinfo_sample_size <= 16)
|
|
{
|
|
int i;
|
|
for (i = 0; i < outputsamples; i++)
|
|
{
|
|
int32_t audiobits_a, audiobits_b;
|
|
|
|
audiobits_a = readbits(alac, alac->setinfo_sample_size);
|
|
audiobits_b = readbits(alac, alac->setinfo_sample_size);
|
|
|
|
audiobits_a = SIGN_EXTENDED32(audiobits_a, alac->setinfo_sample_size);
|
|
audiobits_b = SIGN_EXTENDED32(audiobits_b, alac->setinfo_sample_size);
|
|
|
|
outputsamples_buffer_a[i] = audiobits_a;
|
|
outputsamples_buffer_b[i] = audiobits_b;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
int i;
|
|
for (i = 0; i < outputsamples; i++)
|
|
{
|
|
int32_t audiobits_a, audiobits_b;
|
|
|
|
audiobits_a = readbits(alac, 16);
|
|
audiobits_a = audiobits_a << 16;
|
|
audiobits_a = audiobits_a >> (32 - alac->setinfo_sample_size);
|
|
audiobits_a |= readbits(alac, alac->setinfo_sample_size - 16);
|
|
|
|
audiobits_b = readbits(alac, 16);
|
|
audiobits_b = audiobits_b << 16;
|
|
audiobits_b = audiobits_b >> (32 - alac->setinfo_sample_size);
|
|
audiobits_b |= readbits(alac, alac->setinfo_sample_size - 16);
|
|
|
|
outputsamples_buffer_a[i] = audiobits_a;
|
|
outputsamples_buffer_b[i] = audiobits_b;
|
|
}
|
|
}
|
|
/* wasted_bytes = 0; */
|
|
interlacing_shift = 0;
|
|
interlacing_leftweight = 0;
|
|
}
|
|
|
|
yield();
|
|
|
|
switch(alac->setinfo_sample_size)
|
|
{
|
|
case 16:
|
|
{
|
|
deinterlace_16(outputsamples_buffer_a,
|
|
outputsamples_buffer_b,
|
|
(int16_t*)outbuffer,
|
|
alac->numchannels,
|
|
outputsamples,
|
|
interlacing_shift,
|
|
interlacing_leftweight);
|
|
break;
|
|
}
|
|
case 20:
|
|
case 24:
|
|
case 32:
|
|
//fprintf(stderr, "FIXME: unimplemented sample size %i\n", alac->setinfo_sample_size);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
break;
|
|
}
|
|
}
|
|
return outbuffer;
|
|
}
|
|
|
|
void create_alac(int samplesize, int numchannels, alac_file* alac)
|
|
{
|
|
alac->samplesize = samplesize;
|
|
alac->numchannels = numchannels;
|
|
alac->bytespersample = (samplesize / 8) * numchannels;
|
|
}
|