/*
- * FLAC (Free Lossless Audio Codec) decoder
- * Copyright (c) 2003 Alex Beregszaszi
+ * FLAC common code
+ * Copyright (c) 2009 Justin Ruggles
*
- * This library is free software; you can redistribute it and/or
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * FFmpeg 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 flac.c
- * FLAC (Free Lossless Audio Codec) decoder
- * @author Alex Beregszaszi
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-
-#include "avcodec.h"
-#include "golomb.h"
-
-#define MAX_CHANNELS 8
-#define MAX_BLOCKSIZE 65535
-
-enum channel_order {
- INDEPENDENT,
- LEFT_SIDE,
- RIGHT_SIDE,
- MID_SIDE,
-};
-
-typedef struct FLACContext {
- AVCodecContext *avctx;
- GetBitContext gb;
-
- int min_blocksize, max_blocksize;
- int min_framesize, max_framesize;
- int samplerate, channels;
- int blocksize, last_blocksize;
- int bps, curr_bps;
- enum channel_order order;
- uint8_t *residual[MAX_CHANNELS];
- uint32_t *decoded[MAX_CHANNELS];
-} FLACContext;
+#include "flac.h"
-#define METADATA_TYPE_STREAMINFO 0
-
-static int sample_rate_table[] =
-{ 0, 0, 0, 0,
- 8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
- 0, 0, 0, 0 };
-
-static int sample_size_table[] =
-{ 0, 8, 12, 0, 16, 20, 24, 0 };
-
-static uint64_t get_uvlc(GetBitContext *gb, int is64)
+int ff_flac_get_max_frame_size(int blocksize, int ch, int bps)
{
- uint64_t val = 0;
- int i = 0;
+ /* Technically, there is no limit to FLAC frame size, but an encoder
+ should not write a frame that is larger than if verbatim encoding mode
+ were to be used. */
- while(i++ < 5+is64)
- {
- const int tmp = get_bits(gb, 8);
-
- if (tmp & 0x80)
- val = (val << 7) + tmp - 0x80;
- else
- return (val << 7) + tmp;
- }
- return -1;
-}
+ int count;
-static int flac_decode_init(AVCodecContext * avctx)
-{
- return 0;
-}
-
-static void dump_headers(FLACContext *s)
-{
- printf(" Blocksize: %d .. %d (%d)\n", s->min_blocksize, s->max_blocksize, s->blocksize);
- printf(" Framesize: %d .. %d\n", s->min_framesize, s->max_framesize);
- printf(" Samplerate: %d\n", s->samplerate);
- printf(" Channels: %d\n", s->channels);
- printf(" Bits: %d\n", s->bps);
-}
-
-static void metadata_streaminfo(FLACContext *s)
-{
- int i;
-
- /* mandatory streaminfo */
- s->min_blocksize = get_bits(&s->gb, 16);
- s->max_blocksize = get_bits(&s->gb, 16);
-
- s->min_framesize = get_bits_long(&s->gb, 24);
- s->max_framesize = get_bits_long(&s->gb, 24);
-
- s->samplerate = get_bits_long(&s->gb, 20);
- s->channels = get_bits(&s->gb, 3) + 1;
- s->bps = get_bits(&s->gb, 5) + 1;
-
- s->avctx->channels = s->channels;
- s->avctx->sample_rate = s->samplerate;
-
- skip_bits(&s->gb, 36); /* total num of samples */
-
- skip_bits(&s->gb, 64); /* md5 sum */
- skip_bits(&s->gb, 64); /* md5 sum */
-
- for (i = 0; i < s->channels; i++)
- {
- s->decoded[i] = av_realloc(s->decoded[i], sizeof(uint32_t)*s->max_blocksize);
- s->residual[i] = av_realloc(s->residual[i], sizeof(uint8_t)*s->max_blocksize);
+ count = 16; /* frame header */
+ count += ch * ((7+bps+7)/8); /* subframe headers */
+ if (ch == 2) {
+ /* for stereo, need to account for using decorrelation */
+ count += (( 2*bps+1) * blocksize + 7) / 8;
+ } else {
+ count += ( ch*bps * blocksize + 7) / 8;
}
-}
-
-static int decode_residuals(FLACContext *s, int channel, int pred_order)
-{
- int i, tmp, partition, method_type, rice_order;
- int sample = 0, samples;
-
- method_type = get_bits(&s->gb, 2);
- if (method_type != 0)
- return -1;
-
- rice_order = get_bits(&s->gb, 4);
+ count += 2; /* frame footer */
- samples = (rice_order > 0) ?
- (s->blocksize >> rice_order) : (s->blocksize - pred_order);
-
- for (partition = 0; partition < (1 << rice_order); partition++)
- {
- tmp = get_bits(&s->gb, 4);
- if (tmp == 0)
- {
- i = (!rice_order || partition) ? 0 : pred_order;
- for (; i < samples; i++, sample++)
- s->residual[channel][sample] = get_sr_golomb_flac(&s->gb, tmp, 0, 0);
- printf("zero k\n");
- }
- else if (tmp == 15)
- {
- printf("fixed len partition\n");
- tmp = get_bits(&s->gb, 5);
- i = (!rice_order || partition) ? 0 : pred_order;
- for (; i < samples; i++, sample++)
- s->residual[channel][sample] = get_bits(&s->gb, tmp);
- }
- else
- {
-// printf("rice coded partition\n");
-#if 1
- i = (!rice_order || partition) ? 0 : pred_order;
- for (; i < samples; i++, sample++)
- s->residual[channel][sample] = get_sr_golomb_flac(&s->gb, tmp, 0, 0);
-#else
- i = ((!rice_order || partition) ? samples : samples - pred_order) + sample;
- for (; sample < i; sample++)
- s->residual[channel][sample] = get_ur_golomb(&s->gb, tmp, 0, 0);
-// s->residual[channel][sample] = get_se_golomb(&s->gb);
-#endif
- }
- }
-
- printf("partitions: %d, samples: %d\n", 1 << rice_order, sample);
-
- return 0;
-}
-
-static int decode_subframe_fixed(FLACContext *s, int channel, int pred_order)
-{
- int i;
-
- printf(" SUBFRAME FIXED\n");
-
- /* warm up samples */
- printf(" warm up samples: %d\n", pred_order);
-
- for (i = 0; i < pred_order; i++)
- {
- s->decoded[channel][i] = get_bits(&s->gb, s->curr_bps);
- printf(" %d: %d\n", i, s->decoded[channel][i]);
- }
-
- if (decode_residuals(s, channel, pred_order) < 0)
- return -1;
-
- switch(pred_order)
- {
- case 0:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] = s->residual[channel][i];
- break;
- case 1:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] = s->residual[channel][i] +
- s->decoded[channel][i-1];
- break;
- case 2:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] = s->residual[channel][i] +
- (s->decoded[channel][i-1] << 1) -
- s->decoded[channel][i-2];
- break;
- case 3:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] = s->residual[channel][i] +
- (((s->decoded[channel][i-1] -
- s->decoded[channel][i-2]) << 1) +
- (s->decoded[channel][i-1] -
- s->decoded[channel][i-2])) +
- s->decoded[channel][i-3];
- break;
- case 4:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] = s->residual[channel][i] +
- ((s->decoded[channel][i-1] +
- s->decoded[channel][i-3]) << 2) -
- ((s->decoded[channel][i-2] << 2) +
- (s->decoded[channel][i-2] << 1)) -
- s->decoded[channel][i-4];
- break;
- }
-
- return 0;
-}
-
-static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
-{
- int sum, i, j;
- int coeff_prec, qlevel;
- int coeffs[pred_order];
-
- printf(" SUBFRAME LPC\n");
-
- /* warm up samples */
- printf(" warm up samples: %d\n", pred_order);
-
- for (i = 0; i < pred_order; i++)
- {
- s->decoded[channel][i] = get_bits(&s->gb, s->curr_bps);
- printf(" %d: %d\n", i, s->decoded[channel][i]);
- }
-
- coeff_prec = get_bits(&s->gb, 4) + 1;
- if (coeff_prec == 16)
- {
- printf("invalid coeff precision\n");
- return -1;
- }
- printf(" qlp coeff prec: %d\n", coeff_prec);
- qlevel = get_bits(&s->gb, 5);
- printf(" quant level: %d\n", qlevel);
-
- for (i = 0; i < pred_order; i++)
- {
- coeffs[i] = get_bits(&s->gb, coeff_prec);
- printf(" %d: %d\n", i, coeffs[i]);
- }
-
- if (decode_residuals(s, channel, pred_order) < 0)
- return -1;
-
- for (i = pred_order; i < s->blocksize; i++)
- {
- sum = 0;
- for (j = 0; j < pred_order; j++)
- sum += coeffs[j] * s->decoded[channel][i-j-1];
- s->decoded[channel][i] = s->residual[channel][i] + (sum >> qlevel);
- }
-
- return 0;
+ return count;
}
-
-static inline int decode_subframe(FLACContext *s, int channel)
-{
- int type, wasted = 0;
- int i, tmp;
-
- s->curr_bps = s->bps;
-
- if (get_bits1(&s->gb))
- {
- printf("invalid subframe padding\n");
- return -1;
- }
- type = get_bits(&s->gb, 6);
-// wasted = get_bits1(&s->gb);
-
-// if (wasted)
-// {
-// while (!get_bits1(&s->gb))
-// wasted++;
-// if (wasted)
-// wasted++;
-// s->curr_bps -= wasted;
-// }
-
- if (get_bits1(&s->gb))
- {
- wasted = 1;
- while (!get_bits1(&s->gb))
- wasted++;
- s->curr_bps -= wasted;
- }
-
- if (type == 0)
- {
- printf("coding type: constant\n");
- tmp = get_bits(&s->gb, s->curr_bps);
- for (i = 0; i < s->blocksize; i++)
- s->decoded[channel][i] = tmp;
- }
- else if (type == 1)
- {
- printf("coding type: verbatim\n");
- for (i = 0; i < s->blocksize; i++)
- s->decoded[channel][i] = get_bits(&s->gb, s->curr_bps);
- }
- else if ((type >= 8) && (type <= 12))
- {
- printf("coding type: fixed\n");
- if (decode_subframe_fixed(s, channel, type & ~0x8) < 0)
- return -1;
- }
- else if (type >= 32)
- {
- printf("coding type: lpc\n");
- if (decode_subframe_lpc(s, channel, (type & ~0x20)+1) < 0)
- return -1;
- }
- else
- {
- printf("invalid coding type\n");
- return -1;
- }
-
- if (wasted)
- {
- int i;
- for (i = 0; i < s->blocksize; i++)
- s->decoded[channel][i] <<= wasted;
- }
-
- return 0;
-}
-
-static int decode_frame(FLACContext *s)
-{
- int blocksize_code, sample_rate_code, sample_size_code, assignment, i;
-
- blocksize_code = get_bits(&s->gb, 4);
- if (blocksize_code == 0)
- s->blocksize = s->min_blocksize;
- else if (blocksize_code == 1)
- s->blocksize = 192;
- else if (blocksize_code <= 5)
- s->blocksize = 576 << (blocksize_code - 2);
- else if (blocksize_code >= 8)
- s->blocksize = 256 << (blocksize_code - 8);
-
- sample_rate_code = get_bits(&s->gb, 4);
- if ((sample_rate_code > 3) && (sample_rate_code < 12))
- s->samplerate = sample_rate_table[sample_rate_code];
-
- assignment = get_bits(&s->gb, 4); /* channel assignment */
- if (assignment < 8)
- {
- s->order = INDEPENDENT;
- if (s->channels != assignment+1)
- printf("channel number and number of assigned channels differ!\n");
- printf("channels: %d\n", assignment+1);
- }
- else if (assignment == 8)
- {
- s->order = LEFT_SIDE;
- printf("left/side\n");
- }
- else if (assignment == 9)
- {
- s->order = RIGHT_SIDE;
- printf("right/side\n");
- }
- else if (assignment == 10)
- {
- s->order = MID_SIDE;
- printf("mid/side\n");
- }
- else
- {
- printf("unsupported channel assignment\n");
- return -1;
- }
-
- if ((assignment >= 8) && (s->channels != 2))
- {
- return -1;
- }
-
- sample_size_code = get_bits(&s->gb, 3);
- if (s->bps != 0)
- s->bps = sample_size_table[sample_size_code];
-
- if ((sample_size_code == 3) || (sample_size_code == 7))
- {
- printf("invalid sample size code (%d)\n", sample_size_code);
- return -1;
- }
-
- if (get_bits1(&s->gb))
- {
- printf("broken stream, invalid padding\n");
-// return -1;
- }
-
- if (((blocksize_code == 6) || (blocksize_code == 7)) &&
- (s->min_blocksize != s->max_blocksize))
- {
- get_uvlc(&s->gb, 1);
- }
- else
- get_uvlc(&s->gb, 0);
-
- if (blocksize_code == 6)
- s->blocksize = get_bits(&s->gb, 8)+1;
- if (blocksize_code == 7)
- s->blocksize = get_bits(&s->gb, 16)+1;
-
- if ((sample_rate_code > 11) && (sample_rate_code < 15))
- {
- switch(sample_rate_code)
- {
- case 12:
- s->samplerate = get_bits(&s->gb, 8) * 1000;
- break;
- case 13:
- s->samplerate = get_bits(&s->gb, 16);
- break;
- case 14:
- s->samplerate = get_bits(&s->gb, 16) * 10;
- break;
- }
- }
-
- skip_bits(&s->gb, 8); /* header crc */
-
- dump_headers(s);
-
- /* subframes */
- for (i = 0; i < s->channels; i++)
- {
- if (s->blocksize != s->last_blocksize)
- {
- s->decoded[i] = av_realloc(s->decoded[i], sizeof(uint32_t)*s->blocksize);
- s->residual[i] = av_realloc(s->residual[i], sizeof(uint8_t)*s->blocksize);
- }
- printf("decoded: %x residual: %x\n", s->decoded[i], s->residual[i]);
- if (decode_subframe(s, i) < 0)
- return -1;
- }
-
- align_get_bits(&s->gb);
-
- /* frame footer */
- skip_bits(&s->gb, 16); /* data crc */
-
- return 0;
-}
-
-static int flac_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- uint8_t *buf, int buf_size)
-{
- FLACContext *s = avctx->priv_data;
- int metadata_flag, metadata_type, metadata_size;
- int tmp = 0, i, j = 0;
- int16_t *samples = data, *left, *right;
-
- *data_size = 0;
-
- s->avctx = avctx;
-
- init_get_bits(&s->gb, buf, buf_size*8);
-
- /* fLaC signature (be) */
- if (get_bits_long(&s->gb, 32) == bswap_32(ff_get_fourcc("fLaC")))
- {
- printf("STREAM HEADER\n");
- do {
- metadata_flag = get_bits(&s->gb, 1);
- metadata_type = get_bits(&s->gb, 7);
- metadata_size = get_bits_long(&s->gb, 24);
-
- printf(" metadata block: flag = %d, type = %d, size = %d\n",
- metadata_flag, metadata_type,
- metadata_size);
-
- switch(metadata_type)
- {
- case METADATA_TYPE_STREAMINFO:
- metadata_streaminfo(s);
- dump_headers(s);
- break;
- default:
- while ((metadata_size -= 8) > 0)
- skip_bits(&s->gb, 8);
- }
- } while(metadata_flag != 1);
- }
- else
- {
- init_get_bits(&s->gb, buf, buf_size*8);
- tmp = get_bits(&s->gb, 16);
- if (tmp == 0xfff8)
- printf("FRAME HEADER\n");
-
- if (decode_frame(s) < 0)
- return -1;
- }
-
-#if 0
- /* fix the channel order here */
- if (s->order == MID_SIDE)
- {
- short *left = samples;
- short *right = samples + s->blocksize;
- for (i = 0; i < s->blocksize; i += 2)
- {
- uint32_t x = s->decoded[0][i];
- uint32_t y = s->decoded[0][i+1];
-
- right[i] = x - (y / 2);
- left[i] = right[i] + y;
- }
- *data_size = 2 * s->blocksize;
- }
- else
- {
- for (i = 0; i < s->channels; i++)
- {
- switch(s->order)
- {
- case INDEPENDENT:
- for (j = 0; j < s->blocksize; j++)
- samples[(s->blocksize*i)+j] = s->decoded[i][j];
- break;
- case LEFT_SIDE:
- case RIGHT_SIDE:
- if (i == 0)
- for (j = 0; j < s->blocksize; j++)
- samples[(s->blocksize*i)+j] = s->decoded[0][j];
- else
- for (j = 0; j < s->blocksize; j++)
- samples[(s->blocksize*i)+j] = s->decoded[0][j] - s->decoded[i][j];
- break;
-// case MID_SIDE:
-// printf("mid-side unsupported\n");
- }
- *data_size += s->blocksize;
- }
- }
-#else
- switch(s->order)
- {
- case INDEPENDENT:
- for (i = 0; i < s->channels; i++)
- {
- for (j = 0; j < s->blocksize; j++)
- *(samples++) = s->decoded[i][j];
- *data_size += s->blocksize;
- }
- break;
- case LEFT_SIDE:
- assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- *(samples++) = s->decoded[0][i];
- *(samples++) = s->decoded[0][i] - s->decoded[1][i];
- }
- *data_size = 2*s->blocksize;
- break;
- case RIGHT_SIDE:
- assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- *(samples++) = s->decoded[0][i] + s->decoded[1][i];
- *(samples++) = s->decoded[1][i];
- }
- *data_size = 2*s->blocksize;
- break;
- case MID_SIDE:
- assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- int16_t mid, side;
- mid = s->decoded[0][i];
- side = s->decoded[1][i];
-
- mid <<= 1;
- if (side & 1)
- mid++;
- *(samples++) = (mid + side) >> 1;
- *(samples++) = (mid - side) >> 1;
- }
- *data_size = 2*s->blocksize;
- break;
- }
-#endif
-
-// *data_size = (int8_t *)samples - (int8_t *)data;
- printf("data size: %d\n", *data_size);
-
- s->last_blocksize = s->blocksize;
-
- return (get_bits_count(&s->gb)+7)/8;
-}
-
-static int flac_decode_close(AVCodecContext *avctx)
-{
- FLACContext *s = avctx->priv_data;
- int i;
-
- for (i = 0; i < s->channels; i++)
- {
- if (s->decoded[i])
- av_free(s->decoded[i]);
- if (s->residual[i])
- av_free(s->residual[i]);
- }
-
- return 0;
-}
-
-AVCodec flac_decoder = {
- "flac",
- CODEC_TYPE_AUDIO,
- CODEC_ID_FLAC,
- sizeof(FLACContext),
- flac_decode_init,
- NULL,
- flac_decode_close,
- flac_decode_frame,
-};