[FFmpeg-cvslog] Windows Media Audio Lossless decoder
Mashiat Sarker Shakkhar
git at videolan.org
Sat Mar 3 00:38:31 CET 2012
ffmpeg | branch: master | Mashiat Sarker Shakkhar <shahriman_ams at yahoo.com> | Thu Mar 1 12:43:00 2012 +0000| [9d25f1f6194dba9cfd60c0596aa59ad145d61382] | committer: Diego Biurrun
Windows Media Audio Lossless decoder
Decodes 16-bit WMA Lossless encoded files. 24-bit is not supported yet.
Bitstream parser written by Andreas Öman with contributions from
Baptiste Coudurier and Ulion.
Includes a number of bug-fixes from Benjamin Larsson, Michael Niedermayer and
Konstantin Shishkov, shine and polish by Diego Biurrun.
Signed-off-by: Diego Biurrun <diego at biurrun.de>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=9d25f1f6194dba9cfd60c0596aa59ad145d61382
---
Changelog | 1 +
doc/general.texi | 1 +
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 1 +
libavcodec/version.h | 2 +-
libavcodec/wmalosslessdec.c | 1248 +++++++++++++++++++++++++++++++++++++++++++
6 files changed, 1253 insertions(+), 1 deletions(-)
diff --git a/Changelog b/Changelog
index 9dc2ae9..8703955 100644
--- a/Changelog
+++ b/Changelog
@@ -11,6 +11,7 @@ version <next>:
- Sun Rasterfile Encoder
- remove libpostproc
- ID3v2 attached pictures reading and writing
+- WMA Lossless decoder
version 0.8:
diff --git a/doc/general.texi b/doc/general.texi
index c61951a..9f31081 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -768,6 +768,7 @@ following image formats are supported:
@item Westwood Audio (SND1) @tab @tab X
@item Windows Media Audio 1 @tab X @tab X
@item Windows Media Audio 2 @tab X @tab X
+ at item Windows Media Audio Lossless @tab @tab X
@item Windows Media Audio Pro @tab @tab X
@item Windows Media Audio Voice @tab @tab X
@end multitable
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 53e67dc..33a1974 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -418,6 +418,7 @@ OBJS-$(CONFIG_VP6_DECODER) += vp6.o vp56.o vp56data.o vp56dsp.o \
OBJS-$(CONFIG_VP8_DECODER) += vp8.o vp8dsp.o vp56rac.o
OBJS-$(CONFIG_VQA_DECODER) += vqavideo.o
OBJS-$(CONFIG_WAVPACK_DECODER) += wavpack.o
+OBJS-$(CONFIG_WMALOSSLESS_DECODER) += wmalosslessdec.o wma.o
OBJS-$(CONFIG_WMAPRO_DECODER) += wmaprodec.o wma.o
OBJS-$(CONFIG_WMAV1_DECODER) += wmadec.o wma.o aactab.o
OBJS-$(CONFIG_WMAV1_ENCODER) += wmaenc.o wma.o aactab.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 3d3289c..2844cfc 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -289,6 +289,7 @@ void avcodec_register_all(void)
REGISTER_DECODER (VMDAUDIO, vmdaudio);
REGISTER_ENCDEC (VORBIS, vorbis);
REGISTER_DECODER (WAVPACK, wavpack);
+ REGISTER_DECODER (WMALOSSLESS, wmalossless);
REGISTER_DECODER (WMAPRO, wmapro);
REGISTER_ENCDEC (WMAV1, wmav1);
REGISTER_ENCDEC (WMAV2, wmav2);
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 49f929f..7790f24 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -21,7 +21,7 @@
#define AVCODEC_VERSION_H
#define LIBAVCODEC_VERSION_MAJOR 54
-#define LIBAVCODEC_VERSION_MINOR 4
+#define LIBAVCODEC_VERSION_MINOR 5
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
diff --git a/libavcodec/wmalosslessdec.c b/libavcodec/wmalosslessdec.c
new file mode 100644
index 0000000..d311c39
--- /dev/null
+++ b/libavcodec/wmalosslessdec.c
@@ -0,0 +1,1248 @@
+/*
+ * Windows Media Audio Lossless decoder
+ * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
+ * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
+ * Copyright (c) 2011 Andreas Öman
+ * Copyright (c) 2011 - 2012 Mashiat Sarker Shakkhar
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avcodec.h"
+#include "internal.h"
+#include "get_bits.h"
+#include "put_bits.h"
+#include "wma.h"
+
+/** current decoder limitations */
+#define WMALL_MAX_CHANNELS 8 ///< max number of handled channels
+#define MAX_SUBFRAMES 32 ///< max number of subframes per channel
+#define MAX_BANDS 29 ///< max number of scale factor bands
+#define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
+
+#define WMALL_BLOCK_MIN_BITS 6 ///< log2 of min block size
+#define WMALL_BLOCK_MAX_BITS 12 ///< log2 of max block size
+#define WMALL_BLOCK_MAX_SIZE (1 << WMALL_BLOCK_MAX_BITS) ///< maximum block size
+#define WMALL_BLOCK_SIZES (WMALL_BLOCK_MAX_BITS - WMALL_BLOCK_MIN_BITS + 1) ///< possible block sizes
+
+
+/**
+ * @brief frame-specific decoder context for a single channel
+ */
+typedef struct {
+ int16_t prev_block_len; ///< length of the previous block
+ uint8_t transmit_coefs;
+ uint8_t num_subframes;
+ uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
+ uint16_t subframe_offsets[MAX_SUBFRAMES]; ///< subframe positions in the current frame
+ uint8_t cur_subframe; ///< current subframe number
+ uint16_t decoded_samples; ///< number of already processed samples
+ int quant_step; ///< quantization step for the current subframe
+ int transient_counter; ///< number of transient samples from the beginning of the transient zone
+} WmallChannelCtx;
+
+/**
+ * @brief main decoder context
+ */
+typedef struct WmallDecodeCtx {
+ /* generic decoder variables */
+ AVCodecContext *avctx;
+ AVFrame frame;
+ uint8_t frame_data[MAX_FRAMESIZE + FF_INPUT_BUFFER_PADDING_SIZE]; ///< compressed frame data
+ PutBitContext pb; ///< context for filling the frame_data buffer
+
+ /* frame size dependent frame information (set during initialization) */
+ uint32_t decode_flags; ///< used compression features
+ int len_prefix; ///< frame is prefixed with its length
+ int dynamic_range_compression; ///< frame contains DRC data
+ uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
+ uint16_t samples_per_frame; ///< number of samples to output
+ uint16_t log2_frame_size;
+ int8_t num_channels; ///< number of channels in the stream (same as AVCodecContext.num_channels)
+ int8_t lfe_channel; ///< lfe channel index
+ uint8_t max_num_subframes;
+ uint8_t subframe_len_bits; ///< number of bits used for the subframe length
+ uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
+ uint16_t min_samples_per_subframe;
+
+ /* packet decode state */
+ GetBitContext pgb; ///< bitstream reader context for the packet
+ int next_packet_start; ///< start offset of the next WMA packet in the demuxer packet
+ uint8_t packet_offset; ///< offset to the frame in the packet
+ uint8_t packet_sequence_number; ///< current packet number
+ int num_saved_bits; ///< saved number of bits
+ int frame_offset; ///< frame offset in the bit reservoir
+ int subframe_offset; ///< subframe offset in the bit reservoir
+ uint8_t packet_loss; ///< set in case of bitstream error
+ uint8_t packet_done; ///< set when a packet is fully decoded
+
+ /* frame decode state */
+ uint32_t frame_num; ///< current frame number (not used for decoding)
+ GetBitContext gb; ///< bitstream reader context
+ int buf_bit_size; ///< buffer size in bits
+ int16_t *samples_16; ///< current samplebuffer pointer (16-bit)
+ int16_t *samples_16_end; ///< maximum samplebuffer pointer
+ int *samples_32; ///< current samplebuffer pointer (24-bit)
+ int *samples_32_end; ///< maximum samplebuffer pointer
+ uint8_t drc_gain; ///< gain for the DRC tool
+ int8_t skip_frame; ///< skip output step
+ int8_t parsed_all_subframes; ///< all subframes decoded?
+
+ /* subframe/block decode state */
+ int16_t subframe_len; ///< current subframe length
+ int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
+ int8_t channel_indexes_for_cur_subframe[WMALL_MAX_CHANNELS];
+
+ WmallChannelCtx channel[WMALL_MAX_CHANNELS]; ///< per channel data
+
+ // WMA Lossless-specific
+
+ uint8_t do_arith_coding;
+ uint8_t do_ac_filter;
+ uint8_t do_inter_ch_decorr;
+ uint8_t do_mclms;
+ uint8_t do_lpc;
+
+ int8_t acfilter_order;
+ int8_t acfilter_scaling;
+ int64_t acfilter_coeffs[16];
+ int acfilter_prevvalues[2][16];
+
+ int8_t mclms_order;
+ int8_t mclms_scaling;
+ int16_t mclms_coeffs[128];
+ int16_t mclms_coeffs_cur[4];
+ int16_t mclms_prevvalues[64];
+ int16_t mclms_updates[64];
+ int mclms_recent;
+
+ int movave_scaling;
+ int quant_stepsize;
+
+ struct {
+ int order;
+ int scaling;
+ int coefsend;
+ int bitsend;
+ int16_t coefs[256];
+ int16_t lms_prevvalues[512];
+ int16_t lms_updates[512];
+ int recent;
+ } cdlms[2][9];
+
+ int cdlms_ttl[2];
+
+ int bV3RTM;
+
+ int is_channel_coded[2];
+ int update_speed[2];
+
+ int transient[2];
+ int transient_pos[2];
+ int seekable_tile;
+
+ int ave_sum[2];
+
+ int channel_residues[2][2048];
+
+ int lpc_coefs[2][40];
+ int lpc_order;
+ int lpc_scaling;
+ int lpc_intbits;
+
+ int channel_coeffs[2][2048];
+} WmallDecodeCtx;
+
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ WmallDecodeCtx *s = avctx->priv_data;
+ uint8_t *edata_ptr = avctx->extradata;
+ unsigned int channel_mask;
+ int i, log2_max_num_subframes, num_possible_block_sizes;
+
+ s->avctx = avctx;
+ init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
+
+ if (avctx->extradata_size >= 18) {
+ s->decode_flags = AV_RL16(edata_ptr + 14);
+ channel_mask = AV_RL32(edata_ptr + 2);
+ s->bits_per_sample = AV_RL16(edata_ptr);
+ if (s->bits_per_sample == 16)
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+ else if (s->bits_per_sample == 24) {
+ avctx->sample_fmt = AV_SAMPLE_FMT_S32;
+ av_log_missing_feature(avctx, "bit-depth higher than 16", 0);
+ return AVERROR_PATCHWELCOME;
+ } else {
+ av_log(avctx, AV_LOG_ERROR, "Unknown bit-depth: %d\n",
+ s->bits_per_sample);
+ return AVERROR_INVALIDDATA;
+ }
+ /* dump the extradata */
+ for (i = 0; i < avctx->extradata_size; i++)
+ av_dlog(avctx, AV_LOG_DEBUG, "[%x] ", avctx->extradata[i]);
+ av_dlog(avctx, AV_LOG_DEBUG, "\n");
+
+ } else {
+ av_log_ask_for_sample(avctx, "Unsupported extradata size\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ /* generic init */
+ s->log2_frame_size = av_log2(avctx->block_align) + 4;
+
+ /* frame info */
+ s->skip_frame = 1; /* skip first frame */
+ s->packet_loss = 1;
+ s->len_prefix = s->decode_flags & 0x40;
+
+ /* get frame len */
+ s->samples_per_frame = 1 << ff_wma_get_frame_len_bits(avctx->sample_rate,
+ 3, s->decode_flags);
+
+ /* init previous block len */
+ for (i = 0; i < avctx->channels; i++)
+ s->channel[i].prev_block_len = s->samples_per_frame;
+
+ /* subframe info */
+ log2_max_num_subframes = (s->decode_flags & 0x38) >> 3;
+ s->max_num_subframes = 1 << log2_max_num_subframes;
+ s->max_subframe_len_bit = 0;
+ s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
+
+ num_possible_block_sizes = log2_max_num_subframes + 1;
+ s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
+ s->dynamic_range_compression = s->decode_flags & 0x80;
+ s->bV3RTM = s->decode_flags & 0x100;
+
+ if (s->max_num_subframes > MAX_SUBFRAMES) {
+ av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
+ s->max_num_subframes);
+ return AVERROR_INVALIDDATA;
+ }
+
+ s->num_channels = avctx->channels;
+
+ /* extract lfe channel position */
+ s->lfe_channel = -1;
+
+ if (channel_mask & 8) {
+ unsigned int mask;
+ for (mask = 1; mask < 16; mask <<= 1)
+ if (channel_mask & mask)
+ ++s->lfe_channel;
+ }
+
+ if (s->num_channels < 0) {
+ av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
+ s->num_channels);
+ return AVERROR_INVALIDDATA;
+ } else if (s->num_channels > WMALL_MAX_CHANNELS) {
+ av_log_ask_for_sample(avctx, "unsupported number of channels\n");
+ return AVERROR_PATCHWELCOME;
+ }
+
+ avcodec_get_frame_defaults(&s->frame);
+ avctx->coded_frame = &s->frame;
+ avctx->channel_layout = channel_mask;
+ return 0;
+}
+
+/**
+ * @brief Decode the subframe length.
+ * @param s context
+ * @param offset sample offset in the frame
+ * @return decoded subframe length on success, < 0 in case of an error
+ */
+static int decode_subframe_length(WmallDecodeCtx *s, int offset)
+{
+ int frame_len_ratio, subframe_len, len;
+
+ /* no need to read from the bitstream when only one length is possible */
+ if (offset == s->samples_per_frame - s->min_samples_per_subframe)
+ return s->min_samples_per_subframe;
+
+ len = av_log2(s->max_num_subframes - 1) + 1;
+ frame_len_ratio = get_bits(&s->gb, len);
+ subframe_len = s->min_samples_per_subframe * (frame_len_ratio + 1);
+
+ /* sanity check the length */
+ if (subframe_len < s->min_samples_per_subframe ||
+ subframe_len > s->samples_per_frame) {
+ av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
+ subframe_len);
+ return AVERROR_INVALIDDATA;
+ }
+ return subframe_len;
+}
+
+/**
+ * @brief Decode how the data in the frame is split into subframes.
+ * Every WMA frame contains the encoded data for a fixed number of
+ * samples per channel. The data for every channel might be split
+ * into several subframes. This function will reconstruct the list of
+ * subframes for every channel.
+ *
+ * If the subframes are not evenly split, the algorithm estimates the
+ * channels with the lowest number of total samples.
+ * Afterwards, for each of these channels a bit is read from the
+ * bitstream that indicates if the channel contains a subframe with the
+ * next subframe size that is going to be read from the bitstream or not.
+ * If a channel contains such a subframe, the subframe size gets added to
+ * the channel's subframe list.
+ * The algorithm repeats these steps until the frame is properly divided
+ * between the individual channels.
+ *
+ * @param s context
+ * @return 0 on success, < 0 in case of an error
+ */
+static int decode_tilehdr(WmallDecodeCtx *s)
+{
+ uint16_t num_samples[WMALL_MAX_CHANNELS] = { 0 }; /* sum of samples for all currently known subframes of a channel */
+ uint8_t contains_subframe[WMALL_MAX_CHANNELS]; /* flag indicating if a channel contains the current subframe */
+ int channels_for_cur_subframe = s->num_channels; /* number of channels that contain the current subframe */
+ int fixed_channel_layout = 0; /* flag indicating that all channels use the same subfra2me offsets and sizes */
+ int min_channel_len = 0; /* smallest sum of samples (channels with this length will be processed first) */
+ int c, tile_aligned;
+
+ /* reset tiling information */
+ for (c = 0; c < s->num_channels; c++)
+ s->channel[c].num_subframes = 0;
+
+ tile_aligned = get_bits1(&s->gb);
+ if (s->max_num_subframes == 1 || tile_aligned)
+ fixed_channel_layout = 1;
+
+ /* loop until the frame data is split between the subframes */
+ do {
+ int subframe_len;
+
+ /* check which channels contain the subframe */
+ for (c = 0; c < s->num_channels; c++) {
+ if (num_samples[c] == min_channel_len) {
+ if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
+ (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe)) {
+ contains_subframe[c] = 1;
+ } else {
+ contains_subframe[c] = get_bits1(&s->gb);
+ }
+ } else
+ contains_subframe[c] = 0;
+ }
+
+ /* get subframe length, subframe_len == 0 is not allowed */
+ if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
+ return AVERROR_INVALIDDATA;
+ /* add subframes to the individual channels and find new min_channel_len */
+ min_channel_len += subframe_len;
+ for (c = 0; c < s->num_channels; c++) {
+ WmallChannelCtx *chan = &s->channel[c];
+
+ if (contains_subframe[c]) {
+ if (chan->num_subframes >= MAX_SUBFRAMES) {
+ av_log(s->avctx, AV_LOG_ERROR,
+ "broken frame: num subframes > 31\n");
+ return AVERROR_INVALIDDATA;
+ }
+ chan->subframe_len[chan->num_subframes] = subframe_len;
+ num_samples[c] += subframe_len;
+ ++chan->num_subframes;
+ if (num_samples[c] > s->samples_per_frame) {
+ av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
+ "channel len(%d) > samples_per_frame(%d)\n",
+ num_samples[c], s->samples_per_frame);
+ return AVERROR_INVALIDDATA;
+ }
+ } else if (num_samples[c] <= min_channel_len) {
+ if (num_samples[c] < min_channel_len) {
+ channels_for_cur_subframe = 0;
+ min_channel_len = num_samples[c];
+ }
+ ++channels_for_cur_subframe;
+ }
+ }
+ } while (min_channel_len < s->samples_per_frame);
+
+ for (c = 0; c < s->num_channels; c++) {
+ int i, offset = 0;
+ for (i = 0; i < s->channel[c].num_subframes; i++) {
+ s->channel[c].subframe_offsets[i] = offset;
+ offset += s->channel[c].subframe_len[i];
+ }
+ }
+
+ return 0;
+}
+
+static void decode_ac_filter(WmallDecodeCtx *s)
+{
+ int i;
+ s->acfilter_order = get_bits(&s->gb, 4) + 1;
+ s->acfilter_scaling = get_bits(&s->gb, 4);
+
+ for (i = 0; i < s->acfilter_order; i++)
+ s->acfilter_coeffs[i] = get_bits(&s->gb, s->acfilter_scaling) + 1;
+}
+
+static void decode_mclms(WmallDecodeCtx *s)
+{
+ s->mclms_order = (get_bits(&s->gb, 4) + 1) * 2;
+ s->mclms_scaling = get_bits(&s->gb, 4);
+ if (get_bits1(&s->gb)) {
+ int i, send_coef_bits;
+ int cbits = av_log2(s->mclms_scaling + 1);
+ assert(cbits == my_log2(s->mclms_scaling + 1));
+ if (1 << cbits < s->mclms_scaling + 1)
+ cbits++;
+
+ send_coef_bits = (cbits ? get_bits(&s->gb, cbits) : 0) + 2;
+
+ for (i = 0; i < s->mclms_order * s->num_channels * s->num_channels; i++)
+ s->mclms_coeffs[i] = get_bits(&s->gb, send_coef_bits);
+
+ for (i = 0; i < s->num_channels; i++) {
+ int c;
+ for (c = 0; c < i; c++)
+ s->mclms_coeffs_cur[i * s->num_channels + c] = get_bits(&s->gb, send_coef_bits);
+ }
+ }
+}
+
+static void decode_cdlms(WmallDecodeCtx *s)
+{
+ int c, i;
+ int cdlms_send_coef = get_bits1(&s->gb);
+
+ for (c = 0; c < s->num_channels; c++) {
+ s->cdlms_ttl[c] = get_bits(&s->gb, 3) + 1;
+ for (i = 0; i < s->cdlms_ttl[c]; i++)
+ s->cdlms[c][i].order = (get_bits(&s->gb, 7) + 1) * 8;
+
+ for (i = 0; i < s->cdlms_ttl[c]; i++)
+ s->cdlms[c][i].scaling = get_bits(&s->gb, 4);
+
+ if (cdlms_send_coef) {
+ for (i = 0; i < s->cdlms_ttl[c]; i++) {
+ int cbits, shift_l, shift_r, j;
+ cbits = av_log2(s->cdlms[c][i].order);
+ if ((1 << cbits) < s->cdlms[c][i].order)
+ cbits++;
+ s->cdlms[c][i].coefsend = get_bits(&s->gb, cbits) + 1;
+
+ cbits = av_log2(s->cdlms[c][i].scaling + 1);
+ if ((1 << cbits) < s->cdlms[c][i].scaling + 1)
+ cbits++;
+
+ s->cdlms[c][i].bitsend = get_bits(&s->gb, cbits) + 2;
+ shift_l = 32 - s->cdlms[c][i].bitsend;
+ shift_r = 32 - s->cdlms[c][i].scaling - 2;
+ for (j = 0; j < s->cdlms[c][i].coefsend; j++)
+ s->cdlms[c][i].coefs[j] =
+ (get_bits(&s->gb, s->cdlms[c][i].bitsend) << shift_l) >> shift_r;
+ }
+ }
+ }
+}
+
+static int decode_channel_residues(WmallDecodeCtx *s, int ch, int tile_size)
+{
+ int i = 0;
+ unsigned int ave_mean;
+ s->transient[ch] = get_bits1(&s->gb);
+ if (s->transient[ch]) {
+ s->transient_pos[ch] = get_bits(&s->gb, av_log2(tile_size));
+ if (s->transient_pos[ch])
+ s->transient[ch] = 0;
+ s->channel[ch].transient_counter =
+ FFMAX(s->channel[ch].transient_counter, s->samples_per_frame / 2);
+ } else if (s->channel[ch].transient_counter)
+ s->transient[ch] = 1;
+
+ if (s->seekable_tile) {
+ ave_mean = get_bits(&s->gb, s->bits_per_sample);
+ s->ave_sum[ch] = ave_mean << (s->movave_scaling + 1);
+ }
+
+ if (s->seekable_tile) {
+ if (s->do_inter_ch_decorr)
+ s->channel_residues[ch][0] = get_sbits(&s->gb, s->bits_per_sample + 1);
+ else
+ s->channel_residues[ch][0] = get_sbits(&s->gb, s->bits_per_sample);
+ i++;
+ }
+ for (; i < tile_size; i++) {
+ int quo = 0, rem, rem_bits, residue;
+ while(get_bits1(&s->gb)) {
+ quo++;
+ if (get_bits_left(&s->gb) <= 0)
+ return -1;
+ }
+ if (quo >= 32)
+ quo += get_bits_long(&s->gb, get_bits(&s->gb, 5) + 1);
+
+ ave_mean = (s->ave_sum[ch] + (1 << s->movave_scaling)) >> (s->movave_scaling + 1);
+ if (ave_mean <= 1)
+ residue = quo;
+ else {
+ rem_bits = av_ceil_log2(ave_mean);
+ rem = rem_bits ? get_bits(&s->gb, rem_bits) : 0;
+ residue = (quo << rem_bits) + rem;
+ }
+
+ s->ave_sum[ch] = residue + s->ave_sum[ch] -
+ (s->ave_sum[ch] >> s->movave_scaling);
+
+ if (residue & 1)
+ residue = -(residue >> 1) - 1;
+ else
+ residue = residue >> 1;
+ s->channel_residues[ch][i] = residue;
+ }
+
+ return 0;
+
+}
+
+static void decode_lpc(WmallDecodeCtx *s)
+{
+ int ch, i, cbits;
+ s->lpc_order = get_bits(&s->gb, 5) + 1;
+ s->lpc_scaling = get_bits(&s->gb, 4);
+ s->lpc_intbits = get_bits(&s->gb, 3) + 1;
+ cbits = s->lpc_scaling + s->lpc_intbits;
+ for (ch = 0; ch < s->num_channels; ch++)
+ for (i = 0; i < s->lpc_order; i++)
+ s->lpc_coefs[ch][i] = get_sbits(&s->gb, cbits);
+}
+
+static void clear_codec_buffers(WmallDecodeCtx *s)
+{
+ int ich, ilms;
+
+ memset(s->acfilter_coeffs, 0, sizeof(s->acfilter_coeffs));
+ memset(s->acfilter_prevvalues, 0, sizeof(s->acfilter_prevvalues));
+ memset(s->lpc_coefs, 0, sizeof(s->lpc_coefs));
+
+ memset(s->mclms_coeffs, 0, sizeof(s->mclms_coeffs));
+ memset(s->mclms_coeffs_cur, 0, sizeof(s->mclms_coeffs_cur));
+ memset(s->mclms_prevvalues, 0, sizeof(s->mclms_prevvalues));
+ memset(s->mclms_updates, 0, sizeof(s->mclms_updates));
+
+ for (ich = 0; ich < s->num_channels; ich++) {
+ for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++) {
+ memset(s->cdlms[ich][ilms].coefs, 0,
+ sizeof(s->cdlms[ich][ilms].coefs));
+ memset(s->cdlms[ich][ilms].lms_prevvalues, 0,
+ sizeof(s->cdlms[ich][ilms].lms_prevvalues));
+ memset(s->cdlms[ich][ilms].lms_updates, 0,
+ sizeof(s->cdlms[ich][ilms].lms_updates));
+ }
+ s->ave_sum[ich] = 0;
+ }
+}
+
+/**
+ * @brief Reset filter parameters and transient area at new seekable tile.
+ */
+static void reset_codec(WmallDecodeCtx *s)
+{
+ int ich, ilms;
+ s->mclms_recent = s->mclms_order * s->num_channels;
+ for (ich = 0; ich < s->num_channels; ich++) {
+ for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++)
+ s->cdlms[ich][ilms].recent = s->cdlms[ich][ilms].order;
+ /* first sample of a seekable subframe is considered as the starting of
+ a transient area which is samples_per_frame samples long */
+ s->channel[ich].transient_counter = s->samples_per_frame;
+ s->transient[ich] = 1;
+ s->transient_pos[ich] = 0;
+ }
+}
+
+static void mclms_update(WmallDecodeCtx *s, int icoef, int *pred)
+{
+ int i, j, ich, pred_error;
+ int order = s->mclms_order;
+ int num_channels = s->num_channels;
+ int range = 1 << (s->bits_per_sample - 1);
+
+ for (ich = 0; ich < num_channels; ich++) {
+ pred_error = s->channel_residues[ich][icoef] - pred[ich];
+ if (pred_error > 0) {
+ for (i = 0; i < order * num_channels; i++)
+ s->mclms_coeffs[i + ich * order * num_channels] +=
+ s->mclms_updates[s->mclms_recent + i];
+ for (j = 0; j < ich; j++) {
+ if (s->channel_residues[j][icoef] > 0)
+ s->mclms_coeffs_cur[ich * num_channels + j] += 1;
+ else if (s->channel_residues[j][icoef] < 0)
+ s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
+ }
+ } else if (pred_error < 0) {
+ for (i = 0; i < order * num_channels; i++)
+ s->mclms_coeffs[i + ich * order * num_channels] -=
+ s->mclms_updates[s->mclms_recent + i];
+ for (j = 0; j < ich; j++) {
+ if (s->channel_residues[j][icoef] > 0)
+ s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
+ else if (s->channel_residues[j][icoef] < 0)
+ s->mclms_coeffs_cur[ich * num_channels + j] += 1;
+ }
+ }
+ }
+
+ for (ich = num_channels - 1; ich >= 0; ich--) {
+ s->mclms_recent--;
+ s->mclms_prevvalues[s->mclms_recent] = s->channel_residues[ich][icoef];
+ if (s->channel_residues[ich][icoef] > range - 1)
+ s->mclms_prevvalues[s->mclms_recent] = range - 1;
+ else if (s->channel_residues[ich][icoef] < -range)
+ s->mclms_prevvalues[s->mclms_recent] = -range;
+
+ s->mclms_updates[s->mclms_recent] = 0;
+ if (s->channel_residues[ich][icoef] > 0)
+ s->mclms_updates[s->mclms_recent] = 1;
+ else if (s->channel_residues[ich][icoef] < 0)
+ s->mclms_updates[s->mclms_recent] = -1;
+ }
+
+ if (s->mclms_recent == 0) {
+ memcpy(&s->mclms_prevvalues[order * num_channels],
+ s->mclms_prevvalues,
+ 2 * order * num_channels);
+ memcpy(&s->mclms_updates[order * num_channels],
+ s->mclms_updates,
+ 2 * order * num_channels);
+ s->mclms_recent = num_channels * order;
+ }
+}
+
+static void mclms_predict(WmallDecodeCtx *s, int icoef, int *pred)
+{
+ int ich, i;
+ int order = s->mclms_order;
+ int num_channels = s->num_channels;
+
+ for (ich = 0; ich < num_channels; ich++) {
+ if (!s->is_channel_coded[ich])
+ continue;
+ pred[ich] = 0;
+ for (i = 0; i < order * num_channels; i++)
+ pred[ich] += s->mclms_prevvalues[i + s->mclms_recent] *
+ s->mclms_coeffs[i + order * num_channels * ich];
+ for (i = 0; i < ich; i++)
+ pred[ich] += s->channel_residues[i][icoef] *
+ s->mclms_coeffs_cur[i + num_channels * ich];
+ pred[ich] += 1 << s->mclms_scaling - 1;
+ pred[ich] >>= s->mclms_scaling;
+ s->channel_residues[ich][icoef] += pred[ich];
+ }
+}
+
+static void revert_mclms(WmallDecodeCtx *s, int tile_size)
+{
+ int icoef, pred[WMALL_MAX_CHANNELS] = { 0 };
+ for (icoef = 0; icoef < tile_size; icoef++) {
+ mclms_predict(s, icoef, pred);
+ mclms_update(s, icoef, pred);
+ }
+}
+
+static int lms_predict(WmallDecodeCtx *s, int ich, int ilms)
+{
+ int pred = 0, icoef;
+ int recent = s->cdlms[ich][ilms].recent;
+
+ for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
+ pred += s->cdlms[ich][ilms].coefs[icoef] *
+ s->cdlms[ich][ilms].lms_prevvalues[icoef + recent];
+
+ return pred;
+}
+
+static void lms_update(WmallDecodeCtx *s, int ich, int ilms,
+ int input, int residue)
+{
+ int icoef;
+ int recent = s->cdlms[ich][ilms].recent;
+ int range = 1 << s->bits_per_sample - 1;
+
+ if (residue < 0) {
+ for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
+ s->cdlms[ich][ilms].coefs[icoef] -=
+ s->cdlms[ich][ilms].lms_updates[icoef + recent];
+ } else if (residue > 0) {
+ for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
+ s->cdlms[ich][ilms].coefs[icoef] +=
+ s->cdlms[ich][ilms].lms_updates[icoef + recent];
+ }
+
+ if (recent)
+ recent--;
+ else {
+ memcpy(&s->cdlms[ich][ilms].lms_prevvalues[s->cdlms[ich][ilms].order],
+ s->cdlms[ich][ilms].lms_prevvalues,
+ 2 * s->cdlms[ich][ilms].order);
+ memcpy(&s->cdlms[ich][ilms].lms_updates[s->cdlms[ich][ilms].order],
+ s->cdlms[ich][ilms].lms_updates,
+ 2 * s->cdlms[ich][ilms].order);
+ recent = s->cdlms[ich][ilms].order - 1;
+ }
+
+ s->cdlms[ich][ilms].lms_prevvalues[recent] = av_clip(input, -range, range - 1);
+ if (!input)
+ s->cdlms[ich][ilms].lms_updates[recent] = 0;
+ else if (input < 0)
+ s->cdlms[ich][ilms].lms_updates[recent] = -s->update_speed[ich];
+ else
+ s->cdlms[ich][ilms].lms_updates[recent] = s->update_speed[ich];
+
+ s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 4)] >>= 2;
+ s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 3)] >>= 1;
+ s->cdlms[ich][ilms].recent = recent;
+}
+
+static void use_high_update_speed(WmallDecodeCtx *s, int ich)
+{
+ int ilms, recent, icoef;
+ for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
+ recent = s->cdlms[ich][ilms].recent;
+ if (s->update_speed[ich] == 16)
+ continue;
+ if (s->bV3RTM) {
+ for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
+ s->cdlms[ich][ilms].lms_updates[icoef + recent] *= 2;
+ } else {
+ for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
+ s->cdlms[ich][ilms].lms_updates[icoef] *= 2;
+ }
+ }
+ s->update_speed[ich] = 16;
+}
+
+static void use_normal_update_speed(WmallDecodeCtx *s, int ich)
+{
+ int ilms, recent, icoef;
+ for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
+ recent = s->cdlms[ich][ilms].recent;
+ if (s->update_speed[ich] == 8)
+ continue;
+ if (s->bV3RTM)
+ for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
+ s->cdlms[ich][ilms].lms_updates[icoef + recent] /= 2;
+ else
+ for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
+ s->cdlms[ich][ilms].lms_updates[icoef] /= 2;
+ }
+ s->update_speed[ich] = 8;
+}
+
+static void revert_cdlms(WmallDecodeCtx *s, int ch,
+ int coef_begin, int coef_end)
+{
+ int icoef, pred, ilms, num_lms, residue, input;
+
+ num_lms = s->cdlms_ttl[ch];
+ for (ilms = num_lms - 1; ilms >= 0; ilms--) {
+ for (icoef = coef_begin; icoef < coef_end; icoef++) {
+ pred = 1 << (s->cdlms[ch][ilms].scaling - 1);
+ residue = s->channel_residues[ch][icoef];
+ pred += lms_predict(s, ch, ilms);
+ input = residue + (pred >> s->cdlms[ch][ilms].scaling);
+ lms_update(s, ch, ilms, input, residue);
+ s->channel_residues[ch][icoef] = input;
+ }
+ }
+}
+
+static void revert_inter_ch_decorr(WmallDecodeCtx *s, int tile_size)
+{
+ if (s->num_channels != 2)
+ return;
+ else if (s->is_channel_coded[0] && s->is_channel_coded[1]) {
+ int icoef;
+ for (icoef = 0; icoef < tile_size; icoef++) {
+ s->channel_residues[0][icoef] -= s->channel_residues[1][icoef] >> 1;
+ s->channel_residues[1][icoef] += s->channel_residues[0][icoef];
+ }
+ }
+}
+
+static void revert_acfilter(WmallDecodeCtx *s, int tile_size)
+{
+ int ich, pred, i, j;
+ int64_t *filter_coeffs = s->acfilter_coeffs;
+ int scaling = s->acfilter_scaling;
+ int order = s->acfilter_order;
+
+ for (ich = 0; ich < s->num_channels; ich++) {
+ int *prevvalues = s->acfilter_prevvalues[ich];
+ for (i = 0; i < order; i++) {
+ pred = 0;
+ for (j = 0; j < order; j++) {
+ if (i <= j)
+ pred += filter_coeffs[j] * prevvalues[j - i];
+ else
+ pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
+ }
+ pred >>= scaling;
+ s->channel_residues[ich][i] += pred;
+ }
+ for (i = order; i < tile_size; i++) {
+ pred = 0;
+ for (j = 0; j < order; j++)
+ pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
+ pred >>= scaling;
+ s->channel_residues[ich][i] += pred;
+ }
+ for (j = 0; j < order; j++)
+ prevvalues[j] = s->channel_residues[ich][tile_size - j - 1];
+ }
+}
+
+static int decode_subframe(WmallDecodeCtx *s)
+{
+ int offset = s->samples_per_frame;
+ int subframe_len = s->samples_per_frame;
+ int total_samples = s->samples_per_frame * s->num_channels;
+ int i, j, rawpcm_tile, padding_zeroes;
+
+ s->subframe_offset = get_bits_count(&s->gb);
+
+ /* reset channel context and find the next block offset and size
+ == the next block of the channel with the smallest number of
+ decoded samples */
+ for (i = 0; i < s->num_channels; i++) {
+ if (offset > s->channel[i].decoded_samples) {
+ offset = s->channel[i].decoded_samples;
+ subframe_len =
+ s->channel[i].subframe_len[s->channel[i].cur_subframe];
+ }
+ }
+
+ /* get a list of all channels that contain the estimated block */
+ s->channels_for_cur_subframe = 0;
+ for (i = 0; i < s->num_channels; i++) {
+ const int cur_subframe = s->channel[i].cur_subframe;
+ /* subtract already processed samples */
+ total_samples -= s->channel[i].decoded_samples;
+
+ /* and count if there are multiple subframes that match our profile */
+ if (offset == s->channel[i].decoded_samples &&
+ subframe_len == s->channel[i].subframe_len[cur_subframe]) {
+ total_samples -= s->channel[i].subframe_len[cur_subframe];
+ s->channel[i].decoded_samples +=
+ s->channel[i].subframe_len[cur_subframe];
+ s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
+ ++s->channels_for_cur_subframe;
+ }
+ }
+
+ /* check if the frame will be complete after processing the
+ estimated block */
+ if (!total_samples)
+ s->parsed_all_subframes = 1;
+
+
+ s->seekable_tile = get_bits1(&s->gb);
+ if (s->seekable_tile) {
+ clear_codec_buffers(s);
+
+ s->do_arith_coding = get_bits1(&s->gb);
+ if (s->do_arith_coding) {
+ av_dlog(s->avctx, AV_LOG_DEBUG, "do_arith_coding == 1");
+ abort();
+ }
+ s->do_ac_filter = get_bits1(&s->gb);
+ s->do_inter_ch_decorr = get_bits1(&s->gb);
+ s->do_mclms = get_bits1(&s->gb);
+
+ if (s->do_ac_filter)
+ decode_ac_filter(s);
+
+ if (s->do_mclms)
+ decode_mclms(s);
+
+ decode_cdlms(s);
+ s->movave_scaling = get_bits(&s->gb, 3);
+ s->quant_stepsize = get_bits(&s->gb, 8) + 1;
+
+ reset_codec(s);
+ }
+
+ rawpcm_tile = get_bits1(&s->gb);
+
+ for (i = 0; i < s->num_channels; i++)
+ s->is_channel_coded[i] = 1;
+
+ if (!rawpcm_tile) {
+ for (i = 0; i < s->num_channels; i++)
+ s->is_channel_coded[i] = get_bits1(&s->gb);
+
+ if (s->bV3RTM) {
+ // LPC
+ s->do_lpc = get_bits1(&s->gb);
+ if (s->do_lpc) {
+ decode_lpc(s);
+ av_log_ask_for_sample(s->avctx, "Inverse LPC filter not "
+ "implemented. Expect wrong output.\n");
+ }
+ } else
+ s->do_lpc = 0;
+ }
+
+
+ if (get_bits1(&s->gb))
+ padding_zeroes = get_bits(&s->gb, 5);
+ else
+ padding_zeroes = 0;
+
+ if (rawpcm_tile) {
+ int bits = s->bits_per_sample - padding_zeroes;
+ av_dlog(s->avctx, AV_LOG_DEBUG, "RAWPCM %d bits per sample. "
+ "total %d bits, remain=%d\n", bits,
+ bits * s->num_channels * subframe_len, get_bits_count(&s->gb));
+ for (i = 0; i < s->num_channels; i++)
+ for (j = 0; j < subframe_len; j++)
+ s->channel_coeffs[i][j] = get_sbits(&s->gb, bits);
+ } else {
+ for (i = 0; i < s->num_channels; i++)
+ if (s->is_channel_coded[i]) {
+ decode_channel_residues(s, i, subframe_len);
+ if (s->seekable_tile)
+ use_high_update_speed(s, i);
+ else
+ use_normal_update_speed(s, i);
+ revert_cdlms(s, i, 0, subframe_len);
+ }
+ }
+ if (s->do_mclms)
+ revert_mclms(s, subframe_len);
+ if (s->do_inter_ch_decorr)
+ revert_inter_ch_decorr(s, subframe_len);
+ if (s->do_ac_filter)
+ revert_acfilter(s, subframe_len);
+
+ /* Dequantize */
+ if (s->quant_stepsize != 1)
+ for (i = 0; i < s->num_channels; i++)
+ for (j = 0; j < subframe_len; j++)
+ s->channel_residues[i][j] *= s->quant_stepsize;
+
+ /* Write to proper output buffer depending on bit-depth */
+ for (i = 0; i < subframe_len; i++)
+ for (j = 0; j < s->num_channels; j++) {
+ if (s->bits_per_sample == 16)
+ *s->samples_16++ = (int16_t) s->channel_residues[j][i];
+ else
+ *s->samples_32++ = s->channel_residues[j][i];
+ }
+
+ /* handled one subframe */
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
+ av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
+ return AVERROR_INVALIDDATA;
+ }
+ ++s->channel[c].cur_subframe;
+ }
+ return 0;
+}
+
+/**
+ * @brief Decode one WMA frame.
+ * @param s codec context
+ * @return 0 if the trailer bit indicates that this is the last frame,
+ * 1 if there are additional frames
+ */
+static int decode_frame(WmallDecodeCtx *s)
+{
+ GetBitContext* gb = &s->gb;
+ int more_frames = 0, len = 0, i, ret;
+
+ s->frame.nb_samples = s->samples_per_frame;
+ if ((ret = s->avctx->get_buffer(s->avctx, &s->frame)) < 0) {
+ /* return an error if no frame could be decoded at all */
+ av_log(s->avctx, AV_LOG_ERROR,
+ "not enough space for the output samples\n");
+ s->packet_loss = 1;
+ return ret;
+ }
+ s->samples_16 = (int16_t *)s->frame.data[0];
+ s->samples_32 = (int32_t *)s->frame.data[0];
+
+ /* get frame length */
+ if (s->len_prefix)
+ len = get_bits(gb, s->log2_frame_size);
+
+ /* decode tile information */
+ if (decode_tilehdr(s)) {
+ s->packet_loss = 1;
+ return 0;
+ }
+
+ /* read drc info */
+ if (s->dynamic_range_compression)
+ s->drc_gain = get_bits(gb, 8);
+
+ /* no idea what these are for, might be the number of samples
+ that need to be skipped at the beginning or end of a stream */
+ if (get_bits1(gb)) {
+ int skip;
+
+ /* usually true for the first frame */
+ if (get_bits1(gb)) {
+ skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
+ av_dlog(s->avctx, AV_LOG_DEBUG, "start skip: %i\n", skip);
+ }
+
+ /* sometimes true for the last frame */
+ if (get_bits1(gb)) {
+ skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
+ av_dlog(s->avctx, AV_LOG_DEBUG, "end skip: %i\n", skip);
+ }
+
+ }
+
+ /* reset subframe states */
+ s->parsed_all_subframes = 0;
+ for (i = 0; i < s->num_channels; i++) {
+ s->channel[i].decoded_samples = 0;
+ s->channel[i].cur_subframe = 0;
+ }
+
+ /* decode all subframes */
+ while (!s->parsed_all_subframes) {
+ if (decode_subframe(s) < 0) {
+ s->packet_loss = 1;
+ return 0;
+ }
+ }
+
+ av_dlog(s->avctx, AV_LOG_DEBUG, "Frame done\n");
+
+ if (s->skip_frame)
+ s->skip_frame = 0;
+
+ if (s->len_prefix) {
+ if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
+ /* FIXME: not sure if this is always an error */
+ av_log(s->avctx, AV_LOG_ERROR,
+ "frame[%i] would have to skip %i bits\n", s->frame_num,
+ len - (get_bits_count(gb) - s->frame_offset) - 1);
+ s->packet_loss = 1;
+ return 0;
+ }
+
+ /* skip the rest of the frame data */
+ skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
+ }
+
+ /* decode trailer bit */
+ more_frames = get_bits1(gb);
+ ++s->frame_num;
+ return more_frames;
+}
+
+/**
+ * @brief Calculate remaining input buffer length.
+ * @param s codec context
+ * @param gb bitstream reader context
+ * @return remaining size in bits
+ */
+static int remaining_bits(WmallDecodeCtx *s, GetBitContext *gb)
+{
+ return s->buf_bit_size - get_bits_count(gb);
+}
+
+/**
+ * @brief Fill the bit reservoir with a (partial) frame.
+ * @param s codec context
+ * @param gb bitstream reader context
+ * @param len length of the partial frame
+ * @param append decides whether to reset the buffer or not
+ */
+static void save_bits(WmallDecodeCtx *s, GetBitContext* gb, int len,
+ int append)
+{
+ int buflen;
+ PutBitContext tmp;
+
+ /* when the frame data does not need to be concatenated, the input buffer
+ is reset and additional bits from the previous frame are copied
+ and skipped later so that a fast byte copy is possible */
+
+ if (!append) {
+ s->frame_offset = get_bits_count(gb) & 7;
+ s->num_saved_bits = s->frame_offset;
+ init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
+ }
+
+ buflen = (s->num_saved_bits + len + 8) >> 3;
+
+ if (len <= 0 || buflen > MAX_FRAMESIZE) {
+ av_log_ask_for_sample(s->avctx, "input buffer too small\n");
+ s->packet_loss = 1;
+ return;
+ }
+
+ s->num_saved_bits += len;
+ if (!append) {
+ avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
+ s->num_saved_bits);
+ } else {
+ int align = 8 - (get_bits_count(gb) & 7);
+ align = FFMIN(align, len);
+ put_bits(&s->pb, align, get_bits(gb, align));
+ len -= align;
+ avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
+ }
+ skip_bits_long(gb, len);
+
+ tmp = s->pb;
+ flush_put_bits(&tmp);
+
+ init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
+ skip_bits(&s->gb, s->frame_offset);
+}
+
+/**
+ * @brief Decode a single WMA packet.
+ * @param avctx codec context
+ * @param data the output buffer
+ * @param data_size number of bytes that were written to the output buffer
+ * @param avpkt input packet
+ * @return number of bytes that were read from the input buffer
+ */
+static int decode_packet(AVCodecContext *avctx, void *data, int *got_frame_ptr,
+ AVPacket* avpkt)
+{
+ WmallDecodeCtx *s = avctx->priv_data;
+ GetBitContext* gb = &s->pgb;
+ const uint8_t* buf = avpkt->data;
+ int buf_size = avpkt->size;
+ int num_bits_prev_frame, packet_sequence_number,
+ seekable_frame_in_packet, spliced_packet;
+
+ if (s->packet_done || s->packet_loss) {
+ s->packet_done = 0;
+
+ /* sanity check for the buffer length */
+ if (buf_size < avctx->block_align)
+ return 0;
+
+ s->next_packet_start = buf_size - avctx->block_align;
+ buf_size = avctx->block_align;
+ s->buf_bit_size = buf_size << 3;
+
+ /* parse packet header */
+ init_get_bits(gb, buf, s->buf_bit_size);
+ packet_sequence_number = get_bits(gb, 4);
+ seekable_frame_in_packet = get_bits1(gb);
+ spliced_packet = get_bits1(gb);
+
+ /* get number of bits that need to be added to the previous frame */
+ num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
+
+ /* check for packet loss */
+ if (!s->packet_loss &&
+ ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
+ s->packet_loss = 1;
+ av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
+ s->packet_sequence_number, packet_sequence_number);
+ }
+ s->packet_sequence_number = packet_sequence_number;
+
+ if (num_bits_prev_frame > 0) {
+ int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
+ if (num_bits_prev_frame >= remaining_packet_bits) {
+ num_bits_prev_frame = remaining_packet_bits;
+ s->packet_done = 1;
+ }
+
+ /* Append the previous frame data to the remaining data from the
+ * previous packet to create a full frame. */
+ save_bits(s, gb, num_bits_prev_frame, 1);
+
+ /* decode the cross packet frame if it is valid */
+ if (!s->packet_loss)
+ decode_frame(s);
+ } else if (s->num_saved_bits - s->frame_offset) {
+ av_dlog(avctx, AV_LOG_DEBUG, "ignoring %x previously saved bits\n",
+ s->num_saved_bits - s->frame_offset);
+ }
+
+ if (s->packet_loss) {
+ /* Reset number of saved bits so that the decoder does not start
+ * to decode incomplete frames in the s->len_prefix == 0 case. */
+ s->num_saved_bits = 0;
+ s->packet_loss = 0;
+ }
+
+ } else {
+ int frame_size;
+
+ s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
+ init_get_bits(gb, avpkt->data, s->buf_bit_size);
+ skip_bits(gb, s->packet_offset);
+
+ if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
+ (frame_size = show_bits(gb, s->log2_frame_size)) &&
+ frame_size <= remaining_bits(s, gb)) {
+ save_bits(s, gb, frame_size, 0);
+ s->packet_done = !decode_frame(s);
+ } else if (!s->len_prefix
+ && s->num_saved_bits > get_bits_count(&s->gb)) {
+ /* when the frames do not have a length prefix, we don't know the
+ * compressed length of the individual frames however, we know what
+ * part of a new packet belongs to the previous frame therefore we
+ * save the incoming packet first, then we append the "previous
+ * frame" data from the next packet so that we get a buffer that
+ * only contains full frames */
+ s->packet_done = !decode_frame(s);
+ } else {
+ s->packet_done = 1;
+ }
+ }
+
+ if (s->packet_done && !s->packet_loss &&
+ remaining_bits(s, gb) > 0) {
+ /* save the rest of the data so that it can be decoded
+ * with the next packet */
+ save_bits(s, gb, remaining_bits(s, gb), 0);
+ }
+
+ *(AVFrame *)data = s->frame;
+ *got_frame_ptr = 1;
+ s->packet_offset = get_bits_count(gb) & 7;
+
+ return (s->packet_loss) ? AVERROR_INVALIDDATA : get_bits_count(gb) >> 3;
+}
+
+
+AVCodec ff_wmalossless_decoder = {
+ .name = "wmalossless",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = CODEC_ID_WMALOSSLESS,
+ .priv_data_size = sizeof(WmallDecodeCtx),
+ .init = decode_init,
+ .decode = decode_packet,
+ .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio Lossless"),
+};
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