2 * Wmall compatible decoder
3 * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
4 * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
5 * Copyright (c) 2011 Andreas Ă–man
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 * @brief wmall decoder implementation
27 * Wmall is an MDCT based codec comparable to wma standard or AAC.
28 * The decoding therefore consists of the following steps:
29 * - bitstream decoding
30 * - reconstruction of per-channel data
31 * - rescaling and inverse quantization
33 * - windowing and overlapp-add
35 * The compressed wmall bitstream is split into individual packets.
36 * Every such packet contains one or more wma frames.
37 * The compressed frames may have a variable length and frames may
38 * cross packet boundaries.
39 * Common to all wmall frames is the number of samples that are stored in
41 * The number of samples and a few other decode flags are stored
42 * as extradata that has to be passed to the decoder.
44 * The wmall frames themselves are again split into a variable number of
45 * subframes. Every subframe contains the data for 2^N time domain samples
46 * where N varies between 7 and 12.
48 * Example wmall bitstream (in samples):
50 * || packet 0 || packet 1 || packet 2 packets
51 * ---------------------------------------------------
52 * || frame 0 || frame 1 || frame 2 || frames
53 * ---------------------------------------------------
54 * || | | || | | | || || subframes of channel 0
55 * ---------------------------------------------------
56 * || | | || | | | || || subframes of channel 1
57 * ---------------------------------------------------
59 * The frame layouts for the individual channels of a wma frame does not need
62 * However, if the offsets and lengths of several subframes of a frame are the
63 * same, the subframes of the channels can be grouped.
64 * Every group may then use special coding techniques like M/S stereo coding
65 * to improve the compression ratio. These channel transformations do not
66 * need to be applied to a whole subframe. Instead, they can also work on
67 * individual scale factor bands (see below).
68 * The coefficients that carry the audio signal in the frequency domain
69 * are transmitted as huffman-coded vectors with 4, 2 and 1 elements.
70 * In addition to that, the encoder can switch to a runlevel coding scheme
71 * by transmitting subframe_length / 128 zero coefficients.
73 * Before the audio signal can be converted to the time domain, the
74 * coefficients have to be rescaled and inverse quantized.
75 * A subframe is therefore split into several scale factor bands that get
76 * scaled individually.
77 * Scale factors are submitted for every frame but they might be shared
78 * between the subframes of a channel. Scale factors are initially DPCM-coded.
79 * Once scale factors are shared, the differences are transmitted as runlevel
81 * Every subframe length and offset combination in the frame layout shares a
82 * common quantization factor that can be adjusted for every channel by a
84 * After the inverse quantization, the coefficients get processed by an IMDCT.
85 * The resulting values are then windowed with a sine window and the first half
86 * of the values are added to the second half of the output from the previous
87 * subframe in order to reconstruct the output samples.
97 /** current decoder limitations */
98 #define WMALL_MAX_CHANNELS 8 ///< max number of handled channels
99 #define MAX_SUBFRAMES 32 ///< max number of subframes per channel
100 #define MAX_BANDS 29 ///< max number of scale factor bands
101 #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
103 #define WMALL_BLOCK_MIN_BITS 6 ///< log2 of min block size
104 #define WMALL_BLOCK_MAX_BITS 12 ///< log2 of max block size
105 #define WMALL_BLOCK_MAX_SIZE (1 << WMALL_BLOCK_MAX_BITS) ///< maximum block size
106 #define WMALL_BLOCK_SIZES (WMALL_BLOCK_MAX_BITS - WMALL_BLOCK_MIN_BITS + 1) ///< possible block sizes
110 #define SCALEVLCBITS 8
111 #define VEC4MAXDEPTH ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS)
112 #define VEC2MAXDEPTH ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS)
113 #define VEC1MAXDEPTH ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS)
114 #define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS)
115 #define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS)
117 static float sin64[33]; ///< sinus table for decorrelation
120 * @brief frame specific decoder context for a single channel
123 int16_t prev_block_len; ///< length of the previous block
124 uint8_t transmit_coefs;
125 uint8_t num_subframes;
126 uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
127 uint16_t subframe_offset[MAX_SUBFRAMES]; ///< subframe positions in the current frame
128 uint8_t cur_subframe; ///< current subframe number
129 uint16_t decoded_samples; ///< number of already processed samples
130 uint8_t grouped; ///< channel is part of a group
131 int quant_step; ///< quantization step for the current subframe
132 int8_t reuse_sf; ///< share scale factors between subframes
133 int8_t scale_factor_step; ///< scaling step for the current subframe
134 int max_scale_factor; ///< maximum scale factor for the current subframe
135 int saved_scale_factors[2][MAX_BANDS]; ///< resampled and (previously) transmitted scale factor values
136 int8_t scale_factor_idx; ///< index for the transmitted scale factor values (used for resampling)
137 int* scale_factors; ///< pointer to the scale factor values used for decoding
138 uint8_t table_idx; ///< index in sf_offsets for the scale factor reference block
139 float* coeffs; ///< pointer to the subframe decode buffer
140 uint16_t num_vec_coeffs; ///< number of vector coded coefficients
141 DECLARE_ALIGNED(16, float, out)[WMALL_BLOCK_MAX_SIZE + WMALL_BLOCK_MAX_SIZE / 2]; ///< output buffer
142 int transient_counter; ///< number of transient samples from the beginning of transient zone
146 * @brief channel group for channel transformations
149 uint8_t num_channels; ///< number of channels in the group
150 int8_t transform; ///< transform on / off
151 int8_t transform_band[MAX_BANDS]; ///< controls if the transform is enabled for a certain band
152 float decorrelation_matrix[WMALL_MAX_CHANNELS*WMALL_MAX_CHANNELS];
153 float* channel_data[WMALL_MAX_CHANNELS]; ///< transformation coefficients
157 * @brief main decoder context
159 typedef struct WmallDecodeCtx {
160 /* generic decoder variables */
161 AVCodecContext* avctx; ///< codec context for av_log
162 DSPContext dsp; ///< accelerated DSP functions
163 uint8_t frame_data[MAX_FRAMESIZE +
164 FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
165 PutBitContext pb; ///< context for filling the frame_data buffer
166 FFTContext mdct_ctx[WMALL_BLOCK_SIZES]; ///< MDCT context per block size
167 DECLARE_ALIGNED(16, float, tmp)[WMALL_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
168 float* windows[WMALL_BLOCK_SIZES]; ///< windows for the different block sizes
170 /* frame size dependent frame information (set during initialization) */
171 uint32_t decode_flags; ///< used compression features
172 uint8_t len_prefix; ///< frame is prefixed with its length
173 uint8_t dynamic_range_compression; ///< frame contains DRC data
174 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
175 uint16_t samples_per_frame; ///< number of samples to output
176 uint16_t log2_frame_size;
177 int8_t num_channels; ///< number of channels in the stream (same as AVCodecContext.num_channels)
178 int8_t lfe_channel; ///< lfe channel index
179 uint8_t max_num_subframes;
180 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
181 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
182 uint16_t min_samples_per_subframe;
183 int8_t num_sfb[WMALL_BLOCK_SIZES]; ///< scale factor bands per block size
184 int16_t sfb_offsets[WMALL_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
185 int8_t sf_offsets[WMALL_BLOCK_SIZES][WMALL_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
186 int16_t subwoofer_cutoffs[WMALL_BLOCK_SIZES]; ///< subwoofer cutoff values
188 /* packet decode state */
189 GetBitContext pgb; ///< bitstream reader context for the packet
190 int next_packet_start; ///< start offset of the next wma packet in the demuxer packet
191 uint8_t packet_offset; ///< frame offset in the packet
192 uint8_t packet_sequence_number; ///< current packet number
193 int num_saved_bits; ///< saved number of bits
194 int frame_offset; ///< frame offset in the bit reservoir
195 int subframe_offset; ///< subframe offset in the bit reservoir
196 uint8_t packet_loss; ///< set in case of bitstream error
197 uint8_t packet_done; ///< set when a packet is fully decoded
199 /* frame decode state */
200 uint32_t frame_num; ///< current frame number (not used for decoding)
201 GetBitContext gb; ///< bitstream reader context
202 int buf_bit_size; ///< buffer size in bits
203 int16_t* samples_16; ///< current samplebuffer pointer (16-bit)
204 int16_t* samples_16_end; ///< maximum samplebuffer pointer
205 int *samples_32; ///< current samplebuffer pointer (24-bit)
206 int *samples_32_end; ///< maximum samplebuffer pointer
207 uint8_t drc_gain; ///< gain for the DRC tool
208 int8_t skip_frame; ///< skip output step
209 int8_t parsed_all_subframes; ///< all subframes decoded?
211 /* subframe/block decode state */
212 int16_t subframe_len; ///< current subframe length
213 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
214 int8_t channel_indexes_for_cur_subframe[WMALL_MAX_CHANNELS];
215 int8_t num_bands; ///< number of scale factor bands
216 int8_t transmit_num_vec_coeffs; ///< number of vector coded coefficients is part of the bitstream
217 int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
218 uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
219 int8_t esc_len; ///< length of escaped coefficients
221 uint8_t num_chgroups; ///< number of channel groups
222 WmallChannelGrp chgroup[WMALL_MAX_CHANNELS]; ///< channel group information
224 WmallChannelCtx channel[WMALL_MAX_CHANNELS]; ///< per channel data
228 uint8_t do_arith_coding;
229 uint8_t do_ac_filter;
230 uint8_t do_inter_ch_decorr;
234 int8_t acfilter_order;
235 int8_t acfilter_scaling;
236 int64_t acfilter_coeffs[16];
237 int acfilter_prevvalues[2][16];
240 int8_t mclms_scaling;
241 int16_t mclms_coeffs[128];
242 int16_t mclms_coeffs_cur[4];
243 int mclms_prevvalues[64]; // FIXME: should be 32-bit / 16-bit depending on bit-depth
244 int16_t mclms_updates[64];
256 int lms_prevvalues[512]; // FIXME: see above
257 int16_t lms_updates[512]; // and here too
259 } cdlms[2][9]; /* XXX: Here, 2 is the max. no. of channels allowed,
260 9 is the maximum no. of filters per channel.
261 Question is, why 2 if WMALL_MAX_CHANNELS == 8 */
268 int is_channel_coded[2]; // XXX: same question as above applies here too (and below)
272 int transient_pos[2];
277 int channel_residues[2][2048];
280 int lpc_coefs[2][40];
285 int channel_coeffs[2][2048]; // FIXME: should be 32-bit / 16-bit depending on bit-depth
291 #define dprintf(pctx, ...) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__)
294 static int num_logged_tiles = 0;
295 static int num_logged_subframes = 0;
296 static int num_lms_update_call = 0;
299 *@brief helper function to print the most important members of the context
302 static void av_cold dump_context(WmallDecodeCtx *s)
304 #define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
305 #define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b);
307 PRINT("ed sample bit depth", s->bits_per_sample);
308 PRINT_HEX("ed decode flags", s->decode_flags);
309 PRINT("samples per frame", s->samples_per_frame);
310 PRINT("log2 frame size", s->log2_frame_size);
311 PRINT("max num subframes", s->max_num_subframes);
312 PRINT("len prefix", s->len_prefix);
313 PRINT("num channels", s->num_channels);
316 static void dump_int_buffer(uint8_t *buffer, int size, int length, int delimiter)
320 for (i=0 ; i<length ; i++) {
322 av_log(0, 0, "\n[%d] ", i);
323 av_log(0, 0, "%d, ", *(int16_t *)(buffer + i * size));
329 *@brief Uninitialize the decoder and free all resources.
330 *@param avctx codec context
331 *@return 0 on success, < 0 otherwise
333 static av_cold int decode_end(AVCodecContext *avctx)
335 WmallDecodeCtx *s = avctx->priv_data;
338 for (i = 0; i < WMALL_BLOCK_SIZES; i++)
339 ff_mdct_end(&s->mdct_ctx[i]);
345 *@brief Initialize the decoder.
346 *@param avctx codec context
347 *@return 0 on success, -1 otherwise
349 static av_cold int decode_init(AVCodecContext *avctx)
351 WmallDecodeCtx *s = avctx->priv_data;
352 uint8_t *edata_ptr = avctx->extradata;
353 unsigned int channel_mask;
355 int log2_max_num_subframes;
356 int num_possible_block_sizes;
359 dsputil_init(&s->dsp, avctx);
360 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
362 if (avctx->extradata_size >= 18) {
363 s->decode_flags = AV_RL16(edata_ptr+14);
364 channel_mask = AV_RL32(edata_ptr+2);
365 s->bits_per_sample = AV_RL16(edata_ptr);
366 if (s->bits_per_sample == 16)
367 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
368 else if (s->bits_per_sample == 24)
369 avctx->sample_fmt = AV_SAMPLE_FMT_S32;
371 av_log(avctx, AV_LOG_ERROR, "Unknown bit-depth: %d\n",
373 return AVERROR_INVALIDDATA;
375 /** dump the extradata */
376 for (i = 0; i < avctx->extradata_size; i++)
377 dprintf(avctx, "[%x] ", avctx->extradata[i]);
378 dprintf(avctx, "\n");
381 av_log_ask_for_sample(avctx, "Unknown extradata size\n");
382 return AVERROR_INVALIDDATA;
386 s->log2_frame_size = av_log2(avctx->block_align) + 4;
389 s->skip_frame = 1; /* skip first frame */
391 s->len_prefix = (s->decode_flags & 0x40);
394 s->samples_per_frame = 1 << ff_wma_get_frame_len_bits(avctx->sample_rate,
397 /** init previous block len */
398 for (i = 0; i < avctx->channels; i++)
399 s->channel[i].prev_block_len = s->samples_per_frame;
402 log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
403 s->max_num_subframes = 1 << log2_max_num_subframes;
404 s->max_subframe_len_bit = 0;
405 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
407 num_possible_block_sizes = log2_max_num_subframes + 1;
408 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
409 s->dynamic_range_compression = (s->decode_flags & 0x80);
411 s->bV3RTM = s->decode_flags & 0x100;
413 if (s->max_num_subframes > MAX_SUBFRAMES) {
414 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
415 s->max_num_subframes);
416 return AVERROR_INVALIDDATA;
419 s->num_channels = avctx->channels;
421 /** extract lfe channel position */
424 if (channel_mask & 8) {
426 for (mask = 1; mask < 16; mask <<= 1) {
427 if (channel_mask & mask)
432 if (s->num_channels < 0) {
433 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n", s->num_channels);
434 return AVERROR_INVALIDDATA;
435 } else if (s->num_channels > WMALL_MAX_CHANNELS) {
436 av_log_ask_for_sample(avctx, "unsupported number of channels\n");
437 return AVERROR_PATCHWELCOME;
440 avctx->channel_layout = channel_mask;
445 *@brief Decode the subframe length.
447 *@param offset sample offset in the frame
448 *@return decoded subframe length on success, < 0 in case of an error
450 static int decode_subframe_length(WmallDecodeCtx *s, int offset)
453 int subframe_len, len;
455 /** no need to read from the bitstream when only one length is possible */
456 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
457 return s->min_samples_per_subframe;
459 len = av_log2(s->max_num_subframes - 1) + 1;
460 frame_len_ratio = get_bits(&s->gb, len);
462 subframe_len = s->min_samples_per_subframe * (frame_len_ratio + 1);
464 /** sanity check the length */
465 if (subframe_len < s->min_samples_per_subframe ||
466 subframe_len > s->samples_per_frame) {
467 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
469 return AVERROR_INVALIDDATA;
475 *@brief Decode how the data in the frame is split into subframes.
476 * Every WMA frame contains the encoded data for a fixed number of
477 * samples per channel. The data for every channel might be split
478 * into several subframes. This function will reconstruct the list of
479 * subframes for every channel.
481 * If the subframes are not evenly split, the algorithm estimates the
482 * channels with the lowest number of total samples.
483 * Afterwards, for each of these channels a bit is read from the
484 * bitstream that indicates if the channel contains a subframe with the
485 * next subframe size that is going to be read from the bitstream or not.
486 * If a channel contains such a subframe, the subframe size gets added to
487 * the channel's subframe list.
488 * The algorithm repeats these steps until the frame is properly divided
489 * between the individual channels.
492 *@return 0 on success, < 0 in case of an error
494 static int decode_tilehdr(WmallDecodeCtx *s)
496 uint16_t num_samples[WMALL_MAX_CHANNELS]; /**< sum of samples for all currently known subframes of a channel */
497 uint8_t contains_subframe[WMALL_MAX_CHANNELS]; /**< flag indicating if a channel contains the current subframe */
498 int channels_for_cur_subframe = s->num_channels; /**< number of channels that contain the current subframe */
499 int fixed_channel_layout = 0; /**< flag indicating that all channels use the same subfra2me offsets and sizes */
500 int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
503 /* Should never consume more than 3073 bits (256 iterations for the
504 * while loop when always the minimum amount of 128 samples is substracted
505 * from missing samples in the 8 channel case).
506 * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
509 /** reset tiling information */
510 for (c = 0; c < s->num_channels; c++)
511 s->channel[c].num_subframes = 0;
513 memset(num_samples, 0, sizeof(num_samples));
515 if (s->max_num_subframes == 1 || get_bits1(&s->gb))
516 fixed_channel_layout = 1;
518 /** loop until the frame data is split between the subframes */
522 /** check which channels contain the subframe */
523 for (c = 0; c < s->num_channels; c++) {
524 if (num_samples[c] == min_channel_len) {
525 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
526 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe)) {
527 contains_subframe[c] = 1;
529 contains_subframe[c] = get_bits1(&s->gb);
532 contains_subframe[c] = 0;
535 /** get subframe length, subframe_len == 0 is not allowed */
536 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
537 return AVERROR_INVALIDDATA;
538 /** add subframes to the individual channels and find new min_channel_len */
539 min_channel_len += subframe_len;
540 for (c = 0; c < s->num_channels; c++) {
541 WmallChannelCtx* chan = &s->channel[c];
543 if (contains_subframe[c]) {
544 if (chan->num_subframes >= MAX_SUBFRAMES) {
545 av_log(s->avctx, AV_LOG_ERROR,
546 "broken frame: num subframes > 31\n");
547 return AVERROR_INVALIDDATA;
549 chan->subframe_len[chan->num_subframes] = subframe_len;
550 num_samples[c] += subframe_len;
551 ++chan->num_subframes;
552 if (num_samples[c] > s->samples_per_frame) {
553 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
554 "channel len(%d) > samples_per_frame(%d)\n",
555 num_samples[c], s->samples_per_frame);
556 return AVERROR_INVALIDDATA;
558 } else if (num_samples[c] <= min_channel_len) {
559 if (num_samples[c] < min_channel_len) {
560 channels_for_cur_subframe = 0;
561 min_channel_len = num_samples[c];
563 ++channels_for_cur_subframe;
566 } while (min_channel_len < s->samples_per_frame);
568 for (c = 0; c < s->num_channels; c++) {
571 for (i = 0; i < s->channel[c].num_subframes; i++) {
572 s->channel[c].subframe_offset[i] = offset;
573 offset += s->channel[c].subframe_len[i];
581 static int my_log2(unsigned int i)
583 unsigned int iLog2 = 0;
584 while ((i >> iLog2) > 1)
593 static void decode_ac_filter(WmallDecodeCtx *s)
596 s->acfilter_order = get_bits(&s->gb, 4) + 1;
597 s->acfilter_scaling = get_bits(&s->gb, 4);
599 for(i = 0; i < s->acfilter_order; i++) {
600 s->acfilter_coeffs[i] = get_bits(&s->gb, s->acfilter_scaling) + 1;
608 static void decode_mclms(WmallDecodeCtx *s)
610 s->mclms_order = (get_bits(&s->gb, 4) + 1) * 2;
611 s->mclms_scaling = get_bits(&s->gb, 4);
612 if(get_bits1(&s->gb)) {
616 int cbits = av_log2(s->mclms_scaling + 1);
617 assert(cbits == my_log2(s->mclms_scaling + 1));
618 if(1 << cbits < s->mclms_scaling + 1)
621 send_coef_bits = (cbits ? get_bits(&s->gb, cbits) : 0) + 2;
623 for(i = 0; i < s->mclms_order * s->num_channels * s->num_channels; i++) {
624 s->mclms_coeffs[i] = get_bits(&s->gb, send_coef_bits);
627 for(i = 0; i < s->num_channels; i++) {
629 for(c = 0; c < i; c++) {
630 s->mclms_coeffs_cur[i * s->num_channels + c] = get_bits(&s->gb, send_coef_bits);
640 static void decode_cdlms(WmallDecodeCtx *s)
643 int cdlms_send_coef = get_bits1(&s->gb);
645 for(c = 0; c < s->num_channels; c++) {
646 s->cdlms_ttl[c] = get_bits(&s->gb, 3) + 1;
647 for(i = 0; i < s->cdlms_ttl[c]; i++) {
648 s->cdlms[c][i].order = (get_bits(&s->gb, 7) + 1) * 8;
651 for(i = 0; i < s->cdlms_ttl[c]; i++) {
652 s->cdlms[c][i].scaling = get_bits(&s->gb, 4);
655 if(cdlms_send_coef) {
656 for(i = 0; i < s->cdlms_ttl[c]; i++) {
657 int cbits, shift_l, shift_r, j;
658 cbits = av_log2(s->cdlms[c][i].order);
659 if(1 << cbits < s->cdlms[c][i].order)
661 s->cdlms[c][i].coefsend = get_bits(&s->gb, cbits) + 1;
663 cbits = av_log2(s->cdlms[c][i].scaling + 1);
664 if(1 << cbits < s->cdlms[c][i].scaling + 1)
667 s->cdlms[c][i].bitsend = get_bits(&s->gb, cbits) + 2;
668 shift_l = 32 - s->cdlms[c][i].bitsend;
669 shift_r = 32 - 2 - s->cdlms[c][i].scaling;
670 for(j = 0; j < s->cdlms[c][i].coefsend; j++) {
671 s->cdlms[c][i].coefs[j] =
672 (get_bits(&s->gb, s->cdlms[c][i].bitsend) << shift_l) >> shift_r;
682 static int decode_channel_residues(WmallDecodeCtx *s, int ch, int tile_size)
685 unsigned int ave_mean;
686 s->transient[ch] = get_bits1(&s->gb);
687 if(s->transient[ch]) {
688 s->transient_pos[ch] = get_bits(&s->gb, av_log2(tile_size));
689 if (s->transient_pos[ch])
690 s->transient[ch] = 0;
691 s->channel[ch].transient_counter =
692 FFMAX(s->channel[ch].transient_counter, s->samples_per_frame / 2);
693 } else if (s->channel[ch].transient_counter)
694 s->transient[ch] = 1;
696 if(s->seekable_tile) {
697 ave_mean = get_bits(&s->gb, s->bits_per_sample);
698 s->ave_sum[ch] = ave_mean << (s->movave_scaling + 1);
699 // s->ave_sum[ch] *= 2;
702 if(s->seekable_tile) {
703 if(s->do_inter_ch_decorr)
704 s->channel_residues[ch][0] = get_sbits(&s->gb, s->bits_per_sample + 1);
706 s->channel_residues[ch][0] = get_sbits(&s->gb, s->bits_per_sample);
709 //av_log(0, 0, "%8d: ", num_logged_tiles++);
710 for(; i < tile_size; i++) {
711 int quo = 0, rem, rem_bits, residue;
712 while(get_bits1(&s->gb))
715 quo += get_bits_long(&s->gb, get_bits(&s->gb, 5) + 1);
717 ave_mean = (s->ave_sum[ch] + (1 << s->movave_scaling)) >> (s->movave_scaling + 1);
722 rem_bits = av_ceil_log2(ave_mean);
723 rem = rem_bits ? get_bits(&s->gb, rem_bits) : 0;
724 residue = (quo << rem_bits) + rem;
727 s->ave_sum[ch] = residue + s->ave_sum[ch] - (s->ave_sum[ch] >> s->movave_scaling);
730 residue = -(residue >> 1) - 1;
732 residue = residue >> 1;
733 s->channel_residues[ch][i] = residue;
735 //dump_int_buffer(s->channel_residues[ch], 4, tile_size, 16);
746 decode_lpc(WmallDecodeCtx *s)
749 s->lpc_order = get_bits(&s->gb, 5) + 1;
750 s->lpc_scaling = get_bits(&s->gb, 4);
751 s->lpc_intbits = get_bits(&s->gb, 3) + 1;
752 cbits = s->lpc_scaling + s->lpc_intbits;
753 for(ch = 0; ch < s->num_channels; ch++) {
754 for(i = 0; i < s->lpc_order; i++) {
755 s->lpc_coefs[ch][i] = get_sbits(&s->gb, cbits);
761 static void clear_codec_buffers(WmallDecodeCtx *s)
765 memset(s->acfilter_coeffs , 0, 16 * sizeof(int));
766 memset(s->acfilter_prevvalues, 0, 16 * 2 * sizeof(int)); // may be wrong
767 memset(s->lpc_coefs , 0, 40 * 2 * sizeof(int));
769 memset(s->mclms_coeffs , 0, 128 * sizeof(int16_t));
770 memset(s->mclms_coeffs_cur, 0, 4 * sizeof(int16_t));
771 memset(s->mclms_prevvalues, 0, 64 * sizeof(int));
772 memset(s->mclms_updates , 0, 64 * sizeof(int16_t));
774 for (ich = 0; ich < s->num_channels; ich++) {
775 for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++) {
776 memset(s->cdlms[ich][ilms].coefs , 0, 256 * sizeof(int16_t));
777 memset(s->cdlms[ich][ilms].lms_prevvalues, 0, 512 * sizeof(int));
778 memset(s->cdlms[ich][ilms].lms_updates , 0, 512 * sizeof(int16_t));
785 *@brief Resets filter parameters and transient area at new seekable tile
787 static void reset_codec(WmallDecodeCtx *s)
790 s->mclms_recent = s->mclms_order * s->num_channels;
791 for (ich = 0; ich < s->num_channels; ich++) {
792 for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++)
793 s->cdlms[ich][ilms].recent = s->cdlms[ich][ilms].order;
794 /* first sample of a seekable subframe is considered as the starting of
795 a transient area which is samples_per_frame samples long */
796 s->channel[ich].transient_counter = s->samples_per_frame;
797 s->transient[ich] = 1;
798 s->transient_pos[ich] = 0;
804 static void mclms_update(WmallDecodeCtx *s, int icoef, int *pred)
808 int order = s->mclms_order;
809 int num_channels = s->num_channels;
810 int range = 1 << (s->bits_per_sample - 1);
811 //int bps = s->bits_per_sample > 16 ? 4 : 2; // bytes per sample
813 for (ich = 0; ich < num_channels; ich++) {
814 pred_error = s->channel_residues[ich][icoef] - pred[ich];
815 if (pred_error > 0) {
816 for (i = 0; i < order * num_channels; i++)
817 s->mclms_coeffs[i + ich * order * num_channels] +=
818 s->mclms_updates[s->mclms_recent + i];
819 for (j = 0; j < ich; j++) {
820 if (s->channel_residues[j][icoef] > 0)
821 s->mclms_coeffs_cur[ich * num_channels + j] += 1;
822 else if (s->channel_residues[j][icoef] < 0)
823 s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
825 } else if (pred_error < 0) {
826 for (i = 0; i < order * num_channels; i++)
827 s->mclms_coeffs[i + ich * order * num_channels] -=
828 s->mclms_updates[s->mclms_recent + i];
829 for (j = 0; j < ich; j++) {
830 if (s->channel_residues[j][icoef] > 0)
831 s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
832 else if (s->channel_residues[j][icoef] < 0)
833 s->mclms_coeffs_cur[ich * num_channels + j] += 1;
838 for (ich = num_channels - 1; ich >= 0; ich--) {
840 s->mclms_prevvalues[s->mclms_recent] = s->channel_residues[ich][icoef];
841 if (s->channel_residues[ich][icoef] > range - 1)
842 s->mclms_prevvalues[s->mclms_recent] = range - 1;
843 else if (s->channel_residues[ich][icoef] < -range)
844 s->mclms_prevvalues[s->mclms_recent] = -range;
846 s->mclms_updates[s->mclms_recent] = 0;
847 if (s->channel_residues[ich][icoef] > 0)
848 s->mclms_updates[s->mclms_recent] = 1;
849 else if (s->channel_residues[ich][icoef] < 0)
850 s->mclms_updates[s->mclms_recent] = -1;
853 if (s->mclms_recent == 0) {
854 memcpy(&s->mclms_prevvalues[order * num_channels],
856 4 * order * num_channels);
857 memcpy(&s->mclms_updates[order * num_channels],
859 2 * order * num_channels);
860 s->mclms_recent = num_channels * order;
864 static void mclms_predict(WmallDecodeCtx *s, int icoef, int *pred)
867 int order = s->mclms_order;
868 int num_channels = s->num_channels;
870 for (ich = 0; ich < num_channels; ich++) {
871 if (!s->is_channel_coded[ich])
874 for (i = 0; i < order * num_channels; i++)
875 pred[ich] += s->mclms_prevvalues[i + s->mclms_recent] *
876 s->mclms_coeffs[i + order * num_channels * ich];
877 for (i = 0; i < ich; i++)
878 pred[ich] += s->channel_residues[i][icoef] *
879 s->mclms_coeffs_cur[i + num_channels * ich];
880 pred[ich] += 1 << s->mclms_scaling - 1;
881 pred[ich] >>= s->mclms_scaling;
882 s->channel_residues[ich][icoef] += pred[ich];
886 static void revert_mclms(WmallDecodeCtx *s, int tile_size)
888 int icoef, pred[WMALL_MAX_CHANNELS] = {0};
889 for (icoef = 0; icoef < tile_size; icoef++) {
890 mclms_predict(s, icoef, pred);
891 mclms_update(s, icoef, pred);
895 static int lms_predict(WmallDecodeCtx *s, int ich, int ilms)
899 int recent = s->cdlms[ich][ilms].recent;
901 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
902 pred += s->cdlms[ich][ilms].coefs[icoef] *
903 s->cdlms[ich][ilms].lms_prevvalues[icoef + recent];
905 //pred += (1 << (s->cdlms[ich][ilms].scaling - 1));
906 /* XXX: Table 29 has:
907 iPred >= cdlms[iCh][ilms].scaling;
908 seems to me like a missing > */
909 //pred >>= s->cdlms[ich][ilms].scaling;
913 static void lms_update(WmallDecodeCtx *s, int ich, int ilms, int input, int residue)
916 int recent = s->cdlms[ich][ilms].recent;
917 int range = 1 << s->bits_per_sample - 1;
918 //int bps = s->bits_per_sample > 16 ? 4 : 2; // bytes per sample
921 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
922 s->cdlms[ich][ilms].coefs[icoef] -=
923 s->cdlms[ich][ilms].lms_updates[icoef + recent];
924 } else if (residue > 0) {
925 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
926 s->cdlms[ich][ilms].coefs[icoef] +=
927 s->cdlms[ich][ilms].lms_updates[icoef + recent]; /* spec mistakenly
928 dropped the recent */
934 /* XXX: This memcpy()s will probably fail if a fixed 32-bit buffer is used.
935 follow kshishkov's suggestion of using a union. */
936 memcpy(&s->cdlms[ich][ilms].lms_prevvalues[s->cdlms[ich][ilms].order],
937 s->cdlms[ich][ilms].lms_prevvalues,
938 4 * s->cdlms[ich][ilms].order);
939 memcpy(&s->cdlms[ich][ilms].lms_updates[s->cdlms[ich][ilms].order],
940 s->cdlms[ich][ilms].lms_updates,
941 2 * s->cdlms[ich][ilms].order);
942 recent = s->cdlms[ich][ilms].order - 1;
945 s->cdlms[ich][ilms].lms_prevvalues[recent] = av_clip(input, -range, range - 1);
947 s->cdlms[ich][ilms].lms_updates[recent] = 0;
949 s->cdlms[ich][ilms].lms_updates[recent] = -s->update_speed[ich];
951 s->cdlms[ich][ilms].lms_updates[recent] = s->update_speed[ich];
954 cdlms[iCh][ilms].updates[iRecent + cdlms[iCh][ilms].order >> 4] >>= 2;
955 lms_updates[iCh][ilms][iRecent + cdlms[iCh][ilms].order >> 3] >>= 1;
957 Questions is - are cdlms[iCh][ilms].updates[] and lms_updates[][][] two
958 seperate buffers? Here I've assumed that the two are same which makes
961 s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 4)] >>= 2;
962 s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 3)] >>= 1;
963 s->cdlms[ich][ilms].recent = recent;
966 static void use_high_update_speed(WmallDecodeCtx *s, int ich)
968 int ilms, recent, icoef;
969 for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
970 recent = s->cdlms[ich][ilms].recent;
971 if (s->update_speed[ich] == 16)
974 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
975 s->cdlms[ich][ilms].lms_updates[icoef + recent] *= 2;
977 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
978 s->cdlms[ich][ilms].lms_updates[icoef] *= 2;
981 s->update_speed[ich] = 16;
984 static void use_normal_update_speed(WmallDecodeCtx *s, int ich)
986 int ilms, recent, icoef;
987 for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
988 recent = s->cdlms[ich][ilms].recent;
989 if (s->update_speed[ich] == 8)
992 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
993 s->cdlms[ich][ilms].lms_updates[icoef + recent] /= 2;
995 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
996 s->cdlms[ich][ilms].lms_updates[icoef] /= 2;
999 s->update_speed[ich] = 8;
1002 static void revert_cdlms(WmallDecodeCtx *s, int ch, int coef_begin, int coef_end)
1009 num_lms = s->cdlms_ttl[ch];
1010 for (ilms = num_lms - 1; ilms >= 0; ilms--) {
1011 //s->cdlms[ch][ilms].recent = s->cdlms[ch][ilms].order;
1012 for (icoef = coef_begin; icoef < coef_end; icoef++) {
1013 pred = 1 << (s->cdlms[ch][ilms].scaling - 1);
1014 residue = s->channel_residues[ch][icoef];
1015 pred += lms_predict(s, ch, ilms);
1016 input = residue + (pred >> s->cdlms[ch][ilms].scaling);
1017 lms_update(s, ch, ilms, input, residue);
1018 s->channel_residues[ch][icoef] = input;
1023 static void revert_inter_ch_decorr(WmallDecodeCtx *s, int tile_size)
1026 if (s->num_channels != 2)
1028 else if (s->is_channel_coded[0] && s->is_channel_coded[1]) {
1029 for (icoef = 0; icoef < tile_size; icoef++) {
1030 s->channel_residues[0][icoef] -= s->channel_residues[1][icoef] >> 1;
1031 s->channel_residues[1][icoef] += s->channel_residues[0][icoef];
1036 static void revert_acfilter(WmallDecodeCtx *s, int tile_size)
1041 int64_t *filter_coeffs = s->acfilter_coeffs;
1042 int scaling = s->acfilter_scaling;
1043 int order = s->acfilter_order;
1045 for (ich = 0; ich < s->num_channels; ich++) {
1046 int *prevvalues = s->acfilter_prevvalues[ich];
1047 for (i = 0; i < order; i++) {
1049 for (j = 0; j < order; j++) {
1051 pred += filter_coeffs[j] * prevvalues[j - i];
1053 pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
1056 s->channel_residues[ich][i] += pred;
1058 for (i = order; i < tile_size; i++) {
1060 for (j = 0; j < order; j++)
1061 pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
1063 s->channel_residues[ich][i] += pred;
1065 for (j = 0; j < order; j++)
1066 prevvalues[j] = s->channel_residues[ich][tile_size - j - 1];
1071 *@brief Decode a single subframe (block).
1072 *@param s codec context
1073 *@return 0 on success, < 0 when decoding failed
1075 static int decode_subframe(WmallDecodeCtx *s)
1077 int offset = s->samples_per_frame;
1078 int subframe_len = s->samples_per_frame;
1080 int total_samples = s->samples_per_frame * s->num_channels;
1084 s->subframe_offset = get_bits_count(&s->gb);
1086 /** reset channel context and find the next block offset and size
1087 == the next block of the channel with the smallest number of
1090 for (i = 0; i < s->num_channels; i++) {
1091 s->channel[i].grouped = 0;
1092 if (offset > s->channel[i].decoded_samples) {
1093 offset = s->channel[i].decoded_samples;
1095 s->channel[i].subframe_len[s->channel[i].cur_subframe];
1099 /** get a list of all channels that contain the estimated block */
1100 s->channels_for_cur_subframe = 0;
1101 for (i = 0; i < s->num_channels; i++) {
1102 const int cur_subframe = s->channel[i].cur_subframe;
1103 /** substract already processed samples */
1104 total_samples -= s->channel[i].decoded_samples;
1106 /** and count if there are multiple subframes that match our profile */
1107 if (offset == s->channel[i].decoded_samples &&
1108 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
1109 total_samples -= s->channel[i].subframe_len[cur_subframe];
1110 s->channel[i].decoded_samples +=
1111 s->channel[i].subframe_len[cur_subframe];
1112 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
1113 ++s->channels_for_cur_subframe;
1117 /** check if the frame will be complete after processing the
1120 s->parsed_all_subframes = 1;
1123 s->seekable_tile = get_bits1(&s->gb);
1124 if(s->seekable_tile) {
1125 clear_codec_buffers(s);
1127 s->do_arith_coding = get_bits1(&s->gb);
1128 if(s->do_arith_coding) {
1129 dprintf(s->avctx, "do_arith_coding == 1");
1132 s->do_ac_filter = get_bits1(&s->gb);
1133 s->do_inter_ch_decorr = get_bits1(&s->gb);
1134 s->do_mclms = get_bits1(&s->gb);
1137 decode_ac_filter(s);
1143 s->movave_scaling = get_bits(&s->gb, 3);
1144 s->quant_stepsize = get_bits(&s->gb, 8) + 1;
1149 rawpcm_tile = get_bits1(&s->gb);
1151 for(i = 0; i < s->num_channels; i++) {
1152 s->is_channel_coded[i] = 1;
1157 for(i = 0; i < s->num_channels; i++) {
1158 s->is_channel_coded[i] = get_bits1(&s->gb);
1163 s->do_lpc = get_bits1(&s->gb);
1173 if(get_bits1(&s->gb)) {
1174 padding_zeroes = get_bits(&s->gb, 5);
1181 int bits = s->bits_per_sample - padding_zeroes;
1182 dprintf(s->avctx, "RAWPCM %d bits per sample. total %d bits, remain=%d\n", bits,
1183 bits * s->num_channels * subframe_len, get_bits_count(&s->gb));
1184 for(i = 0; i < s->num_channels; i++) {
1185 for(j = 0; j < subframe_len; j++) {
1186 s->channel_coeffs[i][j] = get_sbits(&s->gb, bits);
1187 // dprintf(s->avctx, "PCM[%d][%d] = 0x%04x\n", i, j, s->channel_coeffs[i][j]);
1191 for(i = 0; i < s->num_channels; i++)
1192 if(s->is_channel_coded[i]) {
1193 decode_channel_residues(s, i, subframe_len);
1194 if (s->seekable_tile)
1195 use_high_update_speed(s, i);
1197 use_normal_update_speed(s, i);
1198 revert_cdlms(s, i, 0, subframe_len);
1202 revert_mclms(s, subframe_len);
1203 if (s->do_inter_ch_decorr)
1204 revert_inter_ch_decorr(s, subframe_len);
1206 revert_acfilter(s, subframe_len);
1209 if (s->quant_stepsize != 1)
1210 for (i = 0; i < s->num_channels; i++)
1211 for (j = 0; j < subframe_len; j++)
1212 s->channel_residues[i][j] *= s->quant_stepsize;
1214 // Write to proper output buffer depending on bit-depth
1215 for (i = 0; i < subframe_len; i++)
1216 for (j = 0; j < s->num_channels; j++) {
1217 if (s->bits_per_sample == 16)
1218 *s->samples_16++ = (int16_t) s->channel_residues[j][i];
1220 *s->samples_32++ = s->channel_residues[j][i];
1223 /** handled one subframe */
1225 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1226 int c = s->channel_indexes_for_cur_subframe[i];
1227 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
1228 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
1229 return AVERROR_INVALIDDATA;
1231 ++s->channel[c].cur_subframe;
1233 num_logged_subframes++;
1238 *@brief Decode one WMA frame.
1239 *@param s codec context
1240 *@return 0 if the trailer bit indicates that this is the last frame,
1241 * 1 if there are additional frames
1243 static int decode_frame(WmallDecodeCtx *s)
1245 GetBitContext* gb = &s->gb;
1246 int more_frames = 0;
1251 /** check for potential output buffer overflow */
1252 if (s->bits_per_sample == 16)
1253 buffer_len = s->samples_16_end - s->samples_16;
1255 buffer_len = s->samples_32_end - s->samples_32;
1256 if (s->num_channels * s->samples_per_frame > buffer_len) {
1257 /** return an error if no frame could be decoded at all */
1258 av_log(s->avctx, AV_LOG_ERROR,
1259 "not enough space for the output samples\n");
1264 /** get frame length */
1266 len = get_bits(gb, s->log2_frame_size);
1268 /** decode tile information */
1269 if (decode_tilehdr(s)) {
1274 /** read drc info */
1275 if (s->dynamic_range_compression) {
1276 s->drc_gain = get_bits(gb, 8);
1279 /** no idea what these are for, might be the number of samples
1280 that need to be skipped at the beginning or end of a stream */
1281 if (get_bits1(gb)) {
1284 /** usually true for the first frame */
1285 if (get_bits1(gb)) {
1286 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1287 dprintf(s->avctx, "start skip: %i\n", skip);
1290 /** sometimes true for the last frame */
1291 if (get_bits1(gb)) {
1292 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1293 dprintf(s->avctx, "end skip: %i\n", skip);
1298 /** reset subframe states */
1299 s->parsed_all_subframes = 0;
1300 for (i = 0; i < s->num_channels; i++) {
1301 s->channel[i].decoded_samples = 0;
1302 s->channel[i].cur_subframe = 0;
1303 s->channel[i].reuse_sf = 0;
1306 /** decode all subframes */
1307 while (!s->parsed_all_subframes) {
1308 if (decode_subframe(s) < 0) {
1314 dprintf(s->avctx, "Frame done\n");
1316 if (s->skip_frame) {
1320 if (s->len_prefix) {
1321 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1322 /** FIXME: not sure if this is always an error */
1323 av_log(s->avctx, AV_LOG_ERROR,
1324 "frame[%i] would have to skip %i bits\n", s->frame_num,
1325 len - (get_bits_count(gb) - s->frame_offset) - 1);
1330 /** skip the rest of the frame data */
1331 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1334 while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
1335 dprintf(s->avctx, "skip1\n");
1340 /** decode trailer bit */
1341 more_frames = get_bits1(gb);
1347 *@brief Calculate remaining input buffer length.
1348 *@param s codec context
1349 *@param gb bitstream reader context
1350 *@return remaining size in bits
1352 static int remaining_bits(WmallDecodeCtx *s, GetBitContext *gb)
1354 return s->buf_bit_size - get_bits_count(gb);
1358 *@brief Fill the bit reservoir with a (partial) frame.
1359 *@param s codec context
1360 *@param gb bitstream reader context
1361 *@param len length of the partial frame
1362 *@param append decides wether to reset the buffer or not
1364 static void save_bits(WmallDecodeCtx *s, GetBitContext* gb, int len,
1369 /** when the frame data does not need to be concatenated, the input buffer
1370 is resetted and additional bits from the previous frame are copyed
1371 and skipped later so that a fast byte copy is possible */
1374 s->frame_offset = get_bits_count(gb) & 7;
1375 s->num_saved_bits = s->frame_offset;
1376 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1379 buflen = (s->num_saved_bits + len + 8) >> 3;
1381 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1382 av_log_ask_for_sample(s->avctx, "input buffer too small\n");
1387 s->num_saved_bits += len;
1389 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1392 int align = 8 - (get_bits_count(gb) & 7);
1393 align = FFMIN(align, len);
1394 put_bits(&s->pb, align, get_bits(gb, align));
1396 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1398 skip_bits_long(gb, len);
1401 PutBitContext tmp = s->pb;
1402 flush_put_bits(&tmp);
1405 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1406 skip_bits(&s->gb, s->frame_offset);
1410 *@brief Decode a single WMA packet.
1411 *@param avctx codec context
1412 *@param data the output buffer
1413 *@param data_size number of bytes that were written to the output buffer
1414 *@param avpkt input packet
1415 *@return number of bytes that were read from the input buffer
1417 static int decode_packet(AVCodecContext *avctx,
1418 void *data, int *data_size, AVPacket* avpkt)
1420 WmallDecodeCtx *s = avctx->priv_data;
1421 GetBitContext* gb = &s->pgb;
1422 const uint8_t* buf = avpkt->data;
1423 int buf_size = avpkt->size;
1424 int num_bits_prev_frame;
1425 int packet_sequence_number;
1426 int seekable_frame_in_packet;
1429 if (s->bits_per_sample == 16) {
1430 s->samples_16 = (int16_t *) data;
1431 s->samples_16_end = (int16_t *) ((int8_t*)data + *data_size);
1433 s->samples_32 = (int *) data;
1434 s->samples_32_end = (int *) ((int8_t*)data + *data_size);
1438 if (s->packet_done || s->packet_loss) {
1441 /** sanity check for the buffer length */
1442 if (buf_size < avctx->block_align)
1445 s->next_packet_start = buf_size - avctx->block_align;
1446 buf_size = avctx->block_align;
1447 s->buf_bit_size = buf_size << 3;
1449 /** parse packet header */
1450 init_get_bits(gb, buf, s->buf_bit_size);
1451 packet_sequence_number = get_bits(gb, 4);
1452 seekable_frame_in_packet = get_bits1(gb);
1453 spliced_packet = get_bits1(gb);
1455 /** get number of bits that need to be added to the previous frame */
1456 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1458 /** check for packet loss */
1459 if (!s->packet_loss &&
1460 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1462 av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
1463 s->packet_sequence_number, packet_sequence_number);
1465 s->packet_sequence_number = packet_sequence_number;
1467 if (num_bits_prev_frame > 0) {
1468 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1469 if (num_bits_prev_frame >= remaining_packet_bits) {
1470 num_bits_prev_frame = remaining_packet_bits;
1474 /** append the previous frame data to the remaining data from the
1475 previous packet to create a full frame */
1476 save_bits(s, gb, num_bits_prev_frame, 1);
1478 /** decode the cross packet frame if it is valid */
1479 if (!s->packet_loss)
1481 } else if (s->num_saved_bits - s->frame_offset) {
1482 dprintf(avctx, "ignoring %x previously saved bits\n",
1483 s->num_saved_bits - s->frame_offset);
1486 if (s->packet_loss) {
1487 /** reset number of saved bits so that the decoder
1488 does not start to decode incomplete frames in the
1489 s->len_prefix == 0 case */
1490 s->num_saved_bits = 0;
1497 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1498 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1499 skip_bits(gb, s->packet_offset);
1501 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1502 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1503 frame_size <= remaining_bits(s, gb)) {
1504 save_bits(s, gb, frame_size, 0);
1505 s->packet_done = !decode_frame(s);
1506 } else if (!s->len_prefix
1507 && s->num_saved_bits > get_bits_count(&s->gb)) {
1508 /** when the frames do not have a length prefix, we don't know
1509 the compressed length of the individual frames
1510 however, we know what part of a new packet belongs to the
1512 therefore we save the incoming packet first, then we append
1513 the "previous frame" data from the next packet so that
1514 we get a buffer that only contains full frames */
1515 s->packet_done = !decode_frame(s);
1521 if (s->packet_done && !s->packet_loss &&
1522 remaining_bits(s, gb) > 0) {
1523 /** save the rest of the data so that it can be decoded
1524 with the next packet */
1525 save_bits(s, gb, remaining_bits(s, gb), 0);
1528 if (s->bits_per_sample == 16)
1529 *data_size = (int8_t *)s->samples_16 - (int8_t *)data;
1531 *data_size = (int8_t *)s->samples_32 - (int8_t *)data;
1532 s->packet_offset = get_bits_count(gb) & 7;
1534 return (s->packet_loss) ? AVERROR_INVALIDDATA : get_bits_count(gb) >> 3;
1538 *@brief Clear decoder buffers (for seeking).
1539 *@param avctx codec context
1541 static void flush(AVCodecContext *avctx)
1543 WmallDecodeCtx *s = avctx->priv_data;
1545 /** reset output buffer as a part of it is used during the windowing of a
1547 for (i = 0; i < s->num_channels; i++)
1548 memset(s->channel[i].out, 0, s->samples_per_frame *
1549 sizeof(*s->channel[i].out));
1555 *@brief wmall decoder
1557 AVCodec ff_wmalossless_decoder = {
1560 CODEC_ID_WMALOSSLESS,
1561 sizeof(WmallDecodeCtx),
1566 .capabilities = CODEC_CAP_SUBFRAMES,
1568 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Lossless"),