From 6d6d7970e7c0ae1bf3f0e015d3c22723ed5b1a28 Mon Sep 17 00:00:00 2001 From: Mike Melanson Date: Sun, 6 Mar 2005 00:43:55 +0000 Subject: [PATCH] first pass at ALAC decoder from David Hammerton; while David's original decoder works great, this decoder is not completely and seamlessly integrated yet with FFmpeg Originally committed as revision 4008 to svn://svn.ffmpeg.org/ffmpeg/trunk --- CREDITS | 1 + libavcodec/Makefile | 5 +- libavcodec/alac.c | 970 +++++++++++++++++++++++++++++++++++++++++++++++++ libavcodec/allcodecs.c | 1 + libavcodec/avcodec.h | 4 +- libavformat/mov.c | 18 + 6 files changed, 996 insertions(+), 3 deletions(-) create mode 100644 libavcodec/alac.c diff --git a/CREDITS b/CREDITS index 41bb8b9..dfcaa55 100644 --- a/CREDITS +++ b/CREDITS @@ -14,6 +14,7 @@ Brian Foley Arpad Gereoffy Philip Gladstone Vladimir Gneushev +David Hammerton Wolfgang Hesseler Falk Hueffner Zdenek Kabelac diff --git a/libavcodec/Makefile b/libavcodec/Makefile index 0ee56e6..25c7adf 100644 --- a/libavcodec/Makefile +++ b/libavcodec/Makefile @@ -1,6 +1,6 @@ # # libavcodec Makefile -# (c) 2000-2003 Fabrice Bellard +# (c) 2000-2005 Fabrice Bellard # include ../config.mak @@ -22,7 +22,8 @@ OBJS= bitstream.o utils.o mem.o allcodecs.o \ smc.o parser.o flicvideo.o truemotion1.o vmdav.o lcl.o qtrle.o g726.o \ flac.o vp3dsp.o integer.o snow.o tscc.o sonic.o ulti.o h264idct.o \ qdrw.o xl.o rangecoder.o png.o pnm.o qpeg.o vc9.o h263.o h261.o \ - msmpeg4.o h263dec.o svq1.o rv10.o wmadec.o indeo3.o shorten.o loco.o + msmpeg4.o h263dec.o svq1.o rv10.o wmadec.o indeo3.o shorten.o loco.o \ + alac.o AMROBJS= ifeq ($(AMR_NB),yes) diff --git a/libavcodec/alac.c b/libavcodec/alac.c new file mode 100644 index 0000000..0523707 --- /dev/null +++ b/libavcodec/alac.c @@ -0,0 +1,970 @@ +/* + * ALAC (Apple Lossless Audio Codec) decoder + * Copyright (c) 2005 David Hammerton + * All rights reserved. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/** + * @file alac.c + * ALAC (Apple Lossless Audio Codec) decoder + * @author 2005 David Hammerton + * + * For more information on the ALAC format, visit: + * http://crazney.net/programs/itunes/alac.html + * + * Note: This decoder expects a 36- (0x24-)byte QuickTime atom to be + * passed through the extradata[_size] fields. This atom is tacked onto + * the end of an 'alac' stsd atom and has the following format: + * bytes 0-3 atom size (0x24), big-endian + * bytes 4-7 atom type ('alac', not the 'alac' tag from start of stsd) + * bytes 8-35 data bytes needed by decoder + */ + + +#include "avcodec.h" + +#define ALAC_EXTRADATA_SIZE 36 + +struct alac_file { + unsigned char *input_buffer; + int input_buffer_index; + int input_buffer_size; + int input_buffer_bitaccumulator; /* used so we can do arbitary + bit reads */ + + int samplesize; + int numchannels; + int bytespersample; + + + /* buffers */ + int32_t *predicterror_buffer_a; + int32_t *predicterror_buffer_b; + + int32_t *outputsamples_buffer_a; + int32_t *outputsamples_buffer_b; + + + /* stuff from setinfo */ + uint32_t setinfo_max_samples_per_frame; /* 0x1000 = 4096 */ /* max samples per frame? */ + uint8_t setinfo_7a; /* 0x00 */ + uint8_t setinfo_sample_size; /* 0x10 */ + uint8_t setinfo_rice_historymult; /* 0x28 */ + uint8_t setinfo_rice_initialhistory; /* 0x0a */ + uint8_t setinfo_rice_kmodifier; /* 0x0e */ + uint8_t setinfo_7f; /* 0x02 */ + uint16_t setinfo_80; /* 0x00ff */ + uint32_t setinfo_82; /* 0x000020e7 */ + uint32_t setinfo_86; /* 0x00069fe4 */ + uint32_t setinfo_8a_rate; /* 0x0000ac44 */ + /* end setinfo stuff */ +}; + +typedef struct alac_file alac_file; + +typedef struct { + + AVCodecContext *avctx; + /* init to 0; first frame decode should initialize from extradata and + * set this to 1 */ + int context_initialized; + + alac_file *alac; +} ALACContext; + +static void allocate_buffers(alac_file *alac) +{ + alac->predicterror_buffer_a = av_malloc(alac->setinfo_max_samples_per_frame * 4); + alac->predicterror_buffer_b = av_malloc(alac->setinfo_max_samples_per_frame * 4); + + alac->outputsamples_buffer_a = av_malloc(alac->setinfo_max_samples_per_frame * 4); + alac->outputsamples_buffer_b = av_malloc(alac->setinfo_max_samples_per_frame * 4); +} + +void alac_set_info(alac_file *alac, char *inputbuffer) +{ + char *ptr = inputbuffer; + + ptr += 4; /* size */ + ptr += 4; /* alac */ + ptr += 4; /* 0 ? */ + + alac->setinfo_max_samples_per_frame = BE_32(ptr); /* buffer size / 2 ? */ + ptr += 4; + alac->setinfo_7a = *ptr++; + alac->setinfo_sample_size = *ptr++; + alac->setinfo_rice_historymult = *ptr++; + alac->setinfo_rice_initialhistory = *ptr++; + alac->setinfo_rice_kmodifier = *ptr++; + alac->setinfo_7f = *ptr++; + alac->setinfo_80 = BE_16(ptr); + ptr += 2; + alac->setinfo_82 = BE_32(ptr); + ptr += 4; + alac->setinfo_86 = BE_32(ptr); + ptr += 4; + alac->setinfo_8a_rate = BE_32(ptr); + ptr += 4; + + allocate_buffers(alac); +} + +/* stream reading */ + +/* supports reading 1 to 16 bits, in big endian format */ +static uint32_t readbits_16(alac_file *alac, int bits) +{ + uint32_t result; + int new_accumulator; + + if (alac->input_buffer_index + 2 >= alac->input_buffer_size) { + av_log(NULL, AV_LOG_INFO, "alac: input buffer went out of bounds (%d >= %d)\n", + alac->input_buffer_index + 2, alac->input_buffer_size); + exit (0); + } + result = (alac->input_buffer[alac->input_buffer_index + 0] << 16) | + (alac->input_buffer[alac->input_buffer_index + 1] << 8) | + (alac->input_buffer[alac->input_buffer_index + 2]); + + /* shift left by the number of bits we've already read, + * so that the top 'n' bits of the 24 bits we read will + * be the return bits */ + result = result << alac->input_buffer_bitaccumulator; + + result = result & 0x00ffffff; + + /* and then only want the top 'n' bits from that, where + * n is 'bits' */ + result = result >> (24 - bits); + + new_accumulator = (alac->input_buffer_bitaccumulator + bits); + + /* increase the buffer pointer if we've read over n bytes. */ + alac->input_buffer_index += (new_accumulator >> 3); + + /* and the remainder goes back into the bit accumulator */ + alac->input_buffer_bitaccumulator = (new_accumulator & 7); + + return result; +} + +/* supports reading 1 to 32 bits, in big endian format */ +static uint32_t readbits(alac_file *alac, int bits) +{ + int32_t result = 0; + + if (bits > 16) { + bits -= 16; + result = readbits_16(alac, 16) << bits; + } + + result |= readbits_16(alac, bits); + + return result; +} + +/* reads a single bit */ +static int readbit(alac_file *alac) +{ + int result; + int new_accumulator; + + if (alac->input_buffer_index >= alac->input_buffer_size) { + av_log(NULL, AV_LOG_INFO, "alac: input buffer went out of bounds (%d >= %d)\n", + alac->input_buffer_index + 2, alac->input_buffer_size); + exit (0); + } + + result = alac->input_buffer[alac->input_buffer_index]; + + result = result << alac->input_buffer_bitaccumulator; + + result = result >> 7 & 1; + + new_accumulator = (alac->input_buffer_bitaccumulator + 1); + + alac->input_buffer_index += (new_accumulator / 8); + + alac->input_buffer_bitaccumulator = (new_accumulator % 8); + + return result; +} + +static void unreadbits(alac_file *alac, int bits) +{ + int new_accumulator = (alac->input_buffer_bitaccumulator - bits); + + alac->input_buffer_index += (new_accumulator >> 3); + + alac->input_buffer_bitaccumulator = (new_accumulator & 7); + if (alac->input_buffer_bitaccumulator < 0) + alac->input_buffer_bitaccumulator *= -1; +} + +/* hideously inefficient. could use a bitmask search, + * alternatively bsr on x86, + */ +static int count_leading_zeros(int32_t input) +{ + int i = 0; + while (!(0x80000000 & input) && i < 32) { + i++; + input = input << 1; + } + return i; +} + +void bastardized_rice_decompress(alac_file *alac, + int32_t *output_buffer, + int output_size, + int readsamplesize, /* arg_10 */ + int rice_initialhistory, /* arg424->b */ + int rice_kmodifier, /* arg424->d */ + int rice_historymult, /* arg424->c */ + int rice_kmodifier_mask /* arg424->e */ + ) +{ + int output_count; + unsigned int history = rice_initialhistory; + int sign_modifier = 0; + + for (output_count = 0; output_count < output_size; output_count++) { + int32_t x = 0; + int32_t x_modified; + int32_t final_val; + + /* read x - number of 1s before 0 represent the rice */ + while (x <= 8 && readbit(alac)) { + x++; + } + + + if (x > 8) { /* RICE THRESHOLD */ + /* use alternative encoding */ + int32_t value; + + value = readbits(alac, readsamplesize); + + /* mask value to readsamplesize size */ + if (readsamplesize != 32) + value &= (0xffffffff >> (32 - readsamplesize)); + + x = value; + } else { + /* standard rice encoding */ + int extrabits; + int k; /* size of extra bits */ + + /* read k, that is bits as is */ + k = 31 - rice_kmodifier - count_leading_zeros((history >> 9) + 3); + + if (k < 0) + k += rice_kmodifier; + else + k = rice_kmodifier; + + if (k != 1) { + extrabits = readbits(alac, k); + + /* multiply x by 2^k - 1, as part of their strange algorithm */ + x = (x << k) - x; + + if (extrabits > 1) { + x += extrabits - 1; + } else + unreadbits(alac, 1); + } + } + + x_modified = sign_modifier + x; + final_val = (x_modified + 1) / 2; + if (x_modified & 1) final_val *= -1; + + output_buffer[output_count] = final_val; + + sign_modifier = 0; + + /* now update the history */ + history += (x_modified * rice_historymult) + - ((history * rice_historymult) >> 9); + + if (x_modified > 0xffff) + history = 0xffff; + + /* special case: there may be compressed blocks of 0 */ + if ((history < 128) && (output_count+1 < output_size)) { + int block_size; + + sign_modifier = 1; + + x = 0; + while (x <= 8 && readbit(alac)) { + x++; + } + + if (x > 8) { + block_size = readbits(alac, 16); + block_size &= 0xffff; + } else { + int k; + int extrabits; + + k = count_leading_zeros(history) + ((history + 16) >> 6 /* / 64 */) - 24; + + extrabits = readbits(alac, k); + + block_size = (((1 << k) - 1) & rice_kmodifier_mask) * x + + extrabits - 1; + + if (extrabits < 2) { + x = 1 - extrabits; + block_size += x; + unreadbits(alac, 1); + } + } + + if (block_size > 0) { + memset(&output_buffer[output_count+1], 0, block_size * 4); + output_count += block_size; + + } + + if (block_size > 0xffff) + sign_modifier = 0; + + history = 0; + } + } +} + +#define SIGN_EXTENDED32(val, bits) ((val << (32 - bits)) >> (32 - bits)) + +#define SIGN_ONLY(v) \ + ((v < 0) ? (-1) : \ + ((v > 0) ? (1) : \ + (0))) + +static void predictor_decompress_fir_adapt(int32_t *error_buffer, + int32_t *buffer_out, + int output_size, + int readsamplesize, + int16_t *predictor_coef_table, + int predictor_coef_num, + int predictor_quantitization) +{ + int i; + + /* first sample always copies */ + *buffer_out = *error_buffer; + + if (!predictor_coef_num) { + if (output_size <= 1) return; + memcpy(buffer_out+1, error_buffer+1, (output_size-1) * 4); + return; + } + + if (predictor_coef_num == 0x1f) { /* 11111 - max value of predictor_coef_num */ + /* second-best case scenario for fir decompression, + * error describes a small difference from the previous sample only + */ + if (output_size <= 1) return; + for (i = 0; i < output_size - 1; i++) { + int32_t prev_value; + int32_t error_value; + + prev_value = buffer_out[i]; + error_value = error_buffer[i+1]; + buffer_out[i+1] = SIGN_EXTENDED32((prev_value + error_value), readsamplesize); + } + return; + } + + /* read warm-up samples */ + if (predictor_coef_num > 0) { + int i; + for (i = 0; i < predictor_coef_num; i++) { + int32_t val; + + val = buffer_out[i] + error_buffer[i+1]; + + val = SIGN_EXTENDED32(val, readsamplesize); + + buffer_out[i+1] = val; + } + } + +#if 0 + /* 4 and 8 are very common cases (the only ones i've seen). these + * should be unrolled and optimised + */ + if (predictor_coef_num == 4) { + /* FIXME: optimised general case */ + return; + } + + if (predictor_coef_table == 8) { + /* FIXME: optimised general case */ + return; + } +#endif + + + /* 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; + int16_t left; + int16_t right; + + midright = buffer_a[i]; + difference = buffer_b[i]; + + + right = midright - ((difference * interlacing_leftweight) >> interlacing_shift); + left = (midright - ((difference * interlacing_leftweight) >> interlacing_shift)) + + difference; + + /* output is always little endian */ +/* + if (host_bigendian) { + be2me_16(left); + be2me_16(right); + } +*/ + + buffer_out[i*numchannels] = left; + buffer_out[i*numchannels + 1] = right; + } + + return; + } + + /* otherwise basic interlacing took place */ + for (i = 0; i < numsamples; i++) { + int16_t left, right; + + left = buffer_a[i]; + right = buffer_b[i]; + + /* output is always little endian */ +/* + if (host_bigendian) { + be2me_16(left); + be2me_16(right); + } +*/ + + buffer_out[i*numchannels] = left; + buffer_out[i*numchannels + 1] = right; + } +} + +int decode_frame(ALACContext *s, alac_file *alac, + unsigned char *inbuffer, + int input_buffer_size, + void *outbuffer, int *outputsize){ + + int channels; + int32_t outputsamples = alac->setinfo_max_samples_per_frame; + + /* initialize from the extradata */ + if (!s->context_initialized) { + if (s->avctx->extradata_size != ALAC_EXTRADATA_SIZE) { + av_log(NULL, AV_LOG_ERROR, "alac: expected %d extradata bytes\n", + ALAC_EXTRADATA_SIZE); + return input_buffer_size; + } + alac_set_info(s->alac, s->avctx->extradata); + s->context_initialized = 1; + } + + + /* setup the stream */ + alac->input_buffer = inbuffer; + alac->input_buffer_index = 0; + alac->input_buffer_size = input_buffer_size; + alac->input_buffer_bitaccumulator = 0; + + 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 */ + int16_t predictor_coef_table[32]; + 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. + */ + av_log(NULL, AV_LOG_ERROR, "FIXME: unimplemented, unhandling of wasted_bytes\n"); + } + + bastardized_rice_decompress(alac, + 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); + + if (prediction_type == 0) { + /* adaptive fir */ + predictor_decompress_fir_adapt(alac->predicterror_buffer_a, + alac->outputsamples_buffer_a, + outputsamples, + readsamplesize, + predictor_coef_table, + predictor_coef_num, + prediction_quantitization); + } else { + av_log(NULL, AV_LOG_ERROR, "FIXME: unhandled prediction 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); + + alac->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); + + alac->outputsamples_buffer_a[i] = audiobits; + } + } + /* wasted_bytes = 0; // unused */ + } + + switch(alac->setinfo_sample_size) { + case 16: { + int i; + for (i = 0; i < outputsamples; i++) { + int16_t sample = alac->outputsamples_buffer_a[i]; + be2me_16(sample); + ((int16_t*)outbuffer)[i * alac->numchannels] = sample; + } + break; + } + case 20: + case 24: + case 32: + av_log(NULL, AV_LOG_ERROR, "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; + + if (!isnotcompressed) { + /* compressed */ + int16_t predictor_coef_table_a[32]; + int predictor_coef_num_a; + int prediction_type_a; + int prediction_quantitization_a; + int ricemodifier_a; + + int16_t predictor_coef_table_b[32]; + 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 */ + av_log(NULL, AV_LOG_ERROR, "FIXME: unimplemented, unhandling of wasted_bytes\n"); + } + + /* channel 1 */ + bastardized_rice_decompress(alac, + 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); + + if (prediction_type_a == 0) { + /* adaptive fir */ + predictor_decompress_fir_adapt(alac->predicterror_buffer_a, + alac->outputsamples_buffer_a, + outputsamples, + readsamplesize, + predictor_coef_table_a, + predictor_coef_num_a, + prediction_quantitization_a); + } else { + /* see mono case */ + av_log(NULL, AV_LOG_ERROR, "FIXME: unhandled prediction type: %i\n", prediction_type_a); + } + + /* channel 2 */ + bastardized_rice_decompress(alac, + 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); + + if (prediction_type_b == 0) { + /* adaptive fir */ + predictor_decompress_fir_adapt(alac->predicterror_buffer_b, + alac->outputsamples_buffer_b, + outputsamples, + readsamplesize, + predictor_coef_table_b, + predictor_coef_num_b, + prediction_quantitization_b); + } else { + av_log(NULL, AV_LOG_ERROR, "FIXME: unhandled prediction 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); + + alac->outputsamples_buffer_a[i] = audiobits_a; + alac->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); + + alac->outputsamples_buffer_a[i] = audiobits_a; + alac->outputsamples_buffer_b[i] = audiobits_b; + } + } + /* wasted_bytes = 0; */ + interlacing_shift = 0; + interlacing_leftweight = 0; + } + + switch(alac->setinfo_sample_size) { + case 16: { + deinterlace_16(alac->outputsamples_buffer_a, + alac->outputsamples_buffer_b, + (int16_t*)outbuffer, + alac->numchannels, + outputsamples, + interlacing_shift, + interlacing_leftweight); + break; + } + case 20: + case 24: + case 32: + av_log(NULL, AV_LOG_ERROR, "FIXME: unimplemented sample size %i\n", alac->setinfo_sample_size); + break; + default: + break; + } + + break; + } + } + +av_log(NULL, AV_LOG_INFO, "buf size = %d, consumed %d\n", + input_buffer_size, alac->input_buffer_index); + + /* avoid infinite loop: if decoder consumed 0 bytes; report all bytes + * consumed */ +// if (alac->input_buffer_index) +// return alac->input_buffer_index; +// else + return input_buffer_size; +} + +static int alac_decode_init(AVCodecContext * avctx) +{ + ALACContext *s = avctx->priv_data; + s->avctx = avctx; + s->context_initialized = 0; + + s->alac = av_malloc(sizeof(alac_file)); + + s->alac->samplesize = s->avctx->bits_per_sample; + s->alac->numchannels = s->avctx->channels; + s->alac->bytespersample = (s->alac->samplesize / 8) * s->alac->numchannels; + + return 0; +} + +static int alac_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + ALACContext *s = avctx->priv_data; + int bytes_consumed = buf_size; + + if (buf) + bytes_consumed = decode_frame(s, s->alac, buf, buf_size, + data, data_size); + + return bytes_consumed; +} + +static int alac_decode_close(AVCodecContext *avctx) +{ + ALACContext *s = avctx->priv_data; + + av_free(s->alac->predicterror_buffer_a); + av_free(s->alac->predicterror_buffer_b); + + av_free(s->alac->outputsamples_buffer_a); + av_free(s->alac->outputsamples_buffer_b); + + return 0; +} + +AVCodec alac_decoder = { + "alac", + CODEC_TYPE_AUDIO, + CODEC_ID_ALAC, + sizeof(ALACContext), + alac_decode_init, + NULL, + alac_decode_close, + alac_decode_frame, +}; diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c index 285cfcf..bd3707b 100644 --- a/libavcodec/allcodecs.c +++ b/libavcodec/allcodecs.c @@ -196,6 +196,7 @@ void avcodec_register_all(void) register_avcodec(&qtrle_decoder); register_avcodec(&flac_decoder); register_avcodec(&shorten_decoder); + register_avcodec(&alac_decoder); #endif /* CONFIG_DECODERS */ #ifdef AMR_NB diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h index b4ab5b3..2c3780f 100644 --- a/libavcodec/avcodec.h +++ b/libavcodec/avcodec.h @@ -17,7 +17,7 @@ extern "C" { #define FFMPEG_VERSION_INT 0x000409 #define FFMPEG_VERSION "0.4.9-pre1" -#define LIBAVCODEC_BUILD 4744 +#define LIBAVCODEC_BUILD 4745 #define LIBAVCODEC_VERSION_INT FFMPEG_VERSION_INT #define LIBAVCODEC_VERSION FFMPEG_VERSION @@ -170,6 +170,7 @@ enum CodecID { CODEC_ID_MPEG2TS= 0x20000, /* _FAKE_ codec to indicate a raw MPEG2 transport stream (only used by libavformat) */ + CODEC_ID_ALAC, }; /* CODEC_ID_MP3LAME is absolete */ @@ -2011,6 +2012,7 @@ extern AVCodec xl_decoder; extern AVCodec qpeg_decoder; extern AVCodec shorten_decoder; extern AVCodec loco_decoder; +extern AVCodec alac_decoder; /* pcm codecs */ #define PCM_CODEC(id, name) \ diff --git a/libavformat/mov.c b/libavformat/mov.c index afa0a23..c0d9cec 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -142,6 +142,7 @@ static const CodecTag mov_audio_tags[] = { { CODEC_ID_AMR_NB, MKTAG('s', 'a', 'm', 'r') }, /* AMR-NB 3gp */ { CODEC_ID_AMR_WB, MKTAG('s', 'a', 'w', 'b') }, /* AMR-WB 3gp */ { CODEC_ID_AC3, MKTAG('m', 's', 0x20, 0x00) }, /* Dolby AC-3 */ + { CODEC_ID_ALAC,MKTAG('a', 'l', 'a', 'c') }, /* Apple Lossless */ { CODEC_ID_NONE, 0 }, }; @@ -1101,6 +1102,23 @@ static int mov_read_stsd(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom) st->codec.channels = (px[1] >> 3) & 15; } } + else if( st->codec.codec_tag == MKTAG( 'a', 'l', 'a', 'c' )) + { + /* Handle alac audio tag + special extradata */ + get_be32(pb); /* version */ + get_be32(pb); + st->codec.channels = get_be16(pb); /* channels */ + st->codec.bits_per_sample = get_be16(pb); /* bits per sample */ + get_be32(pb); + st->codec.sample_rate = get_be16(pb); + get_be16(pb); + + /* fetch the 36-byte extradata needed for alac decoding */ + st->codec.extradata_size = 36; + st->codec.extradata = (uint8_t*) + av_mallocz(st->codec.extradata_size + FF_INPUT_BUFFER_PADDING_SIZE); + get_buffer(pb, st->codec.extradata, st->codec.extradata_size); + } else if(size>=(16+20)) {//16 bytes read, reading atleast 20 more uint16_t version; -- 2.7.4