+/*
+ * Wmapro compatible decoder
+ * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
+ * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * @brief wmapro decoder implementation
+ * Wmapro is an MDCT based codec comparable to wma standard or AAC.
+ * The decoding therefore consists of the following steps:
+ * - bitstream decoding
+ * - reconstruction of per-channel data
+ * - rescaling and inverse quantization
+ * - IMDCT
+ * - windowing and overlapp-add
+ *
+ * The compressed wmapro bitstream is split into individual packets.
+ * Every such packet contains one or more wma frames.
+ * The compressed frames may have a variable length and frames may
+ * cross packet boundaries.
+ * Common to all wmapro frames is the number of samples that are stored in
+ * a frame.
+ * The number of samples and a few other decode flags are stored
+ * as extradata that has to be passed to the decoder.
+ *
+ * The wmapro frames themselves are again split into a variable number of
+ * subframes. Every subframe contains the data for 2^N time domain samples
+ * where N varies between 7 and 12.
+ *
+ * Example wmapro bitstream (in samples):
+ *
+ * || packet 0 || packet 1 || packet 2 packets
+ * ---------------------------------------------------
+ * || frame 0 || frame 1 || frame 2 || frames
+ * ---------------------------------------------------
+ * || | | || | | | || || subframes of channel 0
+ * ---------------------------------------------------
+ * || | | || | | | || || subframes of channel 1
+ * ---------------------------------------------------
+ *
+ * The frame layouts for the individual channels of a wma frame does not need
+ * to be the same.
+ *
+ * However, if the offsets and lengths of several subframes of a frame are the
+ * same, the subframes of the channels can be grouped.
+ * Every group may then use special coding techniques like M/S stereo coding
+ * to improve the compression ratio. These channel transformations do not
+ * need to be applied to a whole subframe. Instead, they can also work on
+ * individual scale factor bands (see below).
+ * The coefficients that carry the audio signal in the frequency domain
+ * are transmitted as huffman-coded vectors with 4, 2 and 1 elements.
+ * In addition to that, the encoder can switch to a runlevel coding scheme
+ * by transmitting subframe_length / 128 zero coefficients.
+ *
+ * Before the audio signal can be converted to the time domain, the
+ * coefficients have to be rescaled and inverse quantized.
+ * A subframe is therefore split into several scale factor bands that get
+ * scaled individually.
+ * Scale factors are submitted for every frame but they might be shared
+ * between the subframes of a channel. Scale factors are initially DPCM-coded.
+ * Once scale factors are shared, the differences are transmitted as runlevel
+ * codes.
+ * Every subframe length and offset combination in the frame layout shares a
+ * common quantization factor that can be adjusted for every channel by a
+ * modifier.
+ * After the inverse quantization, the coefficients get processed by an IMDCT.
+ * The resulting values are then windowed with a sine window and the first half
+ * of the values are added to the second half of the output from the previous
+ * subframe in order to reconstruct the output samples.
+ */
+
+#include "libavutil/intfloat.h"
+#include "libavutil/intreadwrite.h"
+#include "avcodec.h"
+#include "internal.h"
+#include "get_bits.h"
+#include "put_bits.h"
+#include "wmaprodata.h"
+#include "dsputil.h"
+#include "fmtconvert.h"
+#include "sinewin.h"
+#include "wma.h"
+
+/** current decoder limitations */
+#define WMAPRO_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 WMAPRO_BLOCK_MIN_BITS 6 ///< log2 of min block size
+#define WMAPRO_BLOCK_MAX_BITS 12 ///< log2 of max block size
+#define WMAPRO_BLOCK_MAX_SIZE (1 << WMAPRO_BLOCK_MAX_BITS) ///< maximum block size
+#define WMAPRO_BLOCK_SIZES (WMAPRO_BLOCK_MAX_BITS - WMAPRO_BLOCK_MIN_BITS + 1) ///< possible block sizes
+
+
+#define VLCBITS 9
+#define SCALEVLCBITS 8
+#define VEC4MAXDEPTH ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS)
+#define VEC2MAXDEPTH ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS)
+#define VEC1MAXDEPTH ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS)
+#define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS)
+#define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS)
+
+static VLC sf_vlc; ///< scale factor DPCM vlc
+static VLC sf_rl_vlc; ///< scale factor run length vlc
+static VLC vec4_vlc; ///< 4 coefficients per symbol
+static VLC vec2_vlc; ///< 2 coefficients per symbol
+static VLC vec1_vlc; ///< 1 coefficient per symbol
+static VLC coef_vlc[2]; ///< coefficient run length vlc codes
+static float sin64[33]; ///< sinus table for decorrelation
+
+/**
+ * @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_offset[MAX_SUBFRAMES]; ///< subframe positions in the current frame
+ uint8_t cur_subframe; ///< current subframe number
+ uint16_t decoded_samples; ///< number of already processed samples
+ uint8_t grouped; ///< channel is part of a group
+ int quant_step; ///< quantization step for the current subframe
+ int8_t reuse_sf; ///< share scale factors between subframes
+ int8_t scale_factor_step; ///< scaling step for the current subframe
+ int max_scale_factor; ///< maximum scale factor for the current subframe
+ int saved_scale_factors[2][MAX_BANDS]; ///< resampled and (previously) transmitted scale factor values
+ int8_t scale_factor_idx; ///< index for the transmitted scale factor values (used for resampling)
+ int* scale_factors; ///< pointer to the scale factor values used for decoding
+ uint8_t table_idx; ///< index in sf_offsets for the scale factor reference block
+ float* coeffs; ///< pointer to the subframe decode buffer
+ uint16_t num_vec_coeffs; ///< number of vector coded coefficients
+ DECLARE_ALIGNED(32, float, out)[WMAPRO_BLOCK_MAX_SIZE + WMAPRO_BLOCK_MAX_SIZE / 2]; ///< output buffer
+} WMAProChannelCtx;
+
+/**
+ * @brief channel group for channel transformations
+ */
+typedef struct {
+ uint8_t num_channels; ///< number of channels in the group
+ int8_t transform; ///< transform on / off
+ int8_t transform_band[MAX_BANDS]; ///< controls if the transform is enabled for a certain band
+ float decorrelation_matrix[WMAPRO_MAX_CHANNELS*WMAPRO_MAX_CHANNELS];
+ float* channel_data[WMAPRO_MAX_CHANNELS]; ///< transformation coefficients
+} WMAProChannelGrp;
+
+/**
+ * @brief main decoder context
+ */
+typedef struct WMAProDecodeCtx {
+ /* generic decoder variables */
+ AVCodecContext* avctx; ///< codec context for av_log
+ AVFrame frame; ///< AVFrame for decoded output
+ DSPContext dsp; ///< accelerated DSP functions
+ FmtConvertContext fmt_conv;
+ uint8_t frame_data[MAX_FRAMESIZE +
+ FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
+ PutBitContext pb; ///< context for filling the frame_data buffer
+ FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
+ DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
+ float* windows[WMAPRO_BLOCK_SIZES]; ///< windows for the different block sizes
+
+ /* frame size dependent frame information (set during initialization) */
+ uint32_t decode_flags; ///< used compression features
+ uint8_t len_prefix; ///< frame is prefixed with its length
+ uint8_t 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;
+ int8_t num_sfb[WMAPRO_BLOCK_SIZES]; ///< scale factor bands per block size
+ int16_t sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
+ int8_t sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
+ int16_t subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; ///< subwoofer cutoff values
+
+ /* 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; ///< frame offset 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
+ 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[WMAPRO_MAX_CHANNELS];
+ int8_t num_bands; ///< number of scale factor bands
+ int8_t transmit_num_vec_coeffs; ///< number of vector coded coefficients is part of the bitstream
+ int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
+ uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
+ int8_t esc_len; ///< length of escaped coefficients
+
+ uint8_t num_chgroups; ///< number of channel groups
+ WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS]; ///< channel group information
+
+ WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS]; ///< per channel data
+} WMAProDecodeCtx;
+
+
+/**
+ *@brief helper function to print the most important members of the context
+ *@param s context
+ */
+static void av_cold dump_context(WMAProDecodeCtx *s)
+{
+#define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
+#define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b);
+
+ PRINT("ed sample bit depth", s->bits_per_sample);
+ PRINT_HEX("ed decode flags", s->decode_flags);
+ PRINT("samples per frame", s->samples_per_frame);
+ PRINT("log2 frame size", s->log2_frame_size);
+ PRINT("max num subframes", s->max_num_subframes);
+ PRINT("len prefix", s->len_prefix);
+ PRINT("num channels", s->num_channels);
+}
+
/**
*@brief Uninitialize the decoder and free all resources.
*@param avctx codec context
*/
static av_cold int decode_end(AVCodecContext *avctx)
{
- WMA3DecodeContext *s = avctx->priv_data;
+ WMAProDecodeCtx *s = avctx->priv_data;
int i;
- av_freep(&s->num_sfb);
- av_freep(&s->sfb_offsets);
- av_freep(&s->subwoofer_cutoffs);
- av_freep(&s->sf_offsets);
-
- for (i=0 ; i<WMAPRO_BLOCK_SIZES ; i++)
+ for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
ff_mdct_end(&s->mdct_ctx[i]);
return 0;
}
+/**
+ *@brief Initialize the decoder.
+ *@param avctx codec context
+ *@return 0 on success, -1 otherwise
+ */
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ WMAProDecodeCtx *s = avctx->priv_data;
+ uint8_t *edata_ptr = avctx->extradata;
+ unsigned int channel_mask;
+ int i;
+ int log2_max_num_subframes;
+ int num_possible_block_sizes;
+
+ s->avctx = avctx;
+ dsputil_init(&s->dsp, avctx);
+ ff_fmt_convert_init(&s->fmt_conv, avctx);
+ init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
+
+ avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
+
+ 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);
+ /** dump the extradata */
+ for (i = 0; i < avctx->extradata_size; i++)
+ av_dlog(avctx, "[%x] ", avctx->extradata[i]);
+ av_dlog(avctx, "\n");
+
+ } else {
+ av_log_ask_for_sample(avctx, "Unknown 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);
+
+ /** subframe info */
+ log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
+ s->max_num_subframes = 1 << log2_max_num_subframes;
+ if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
+ s->max_subframe_len_bit = 1;
+ 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);
+
+ 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;
+
+ 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 > WMAPRO_MAX_CHANNELS) {
+ av_log_ask_for_sample(avctx, "unsupported number of channels\n");
+ return AVERROR_PATCHWELCOME;
+ }
+
+ /** init previous block len */
+ for (i = 0; i < s->num_channels; i++)
+ s->channel[i].prev_block_len = s->samples_per_frame;
+
+ /** 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;
+ }
+ }
+
+ INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
+ scale_huffbits, 1, 1,
+ scale_huffcodes, 2, 2, 616);
+
+ INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
+ scale_rl_huffbits, 1, 1,
+ scale_rl_huffcodes, 4, 4, 1406);
+
+ INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
+ coef0_huffbits, 1, 1,
+ coef0_huffcodes, 4, 4, 2108);
+
+ INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
+ coef1_huffbits, 1, 1,
+ coef1_huffcodes, 4, 4, 3912);
+
+ INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
+ vec4_huffbits, 1, 1,
+ vec4_huffcodes, 2, 2, 604);
+
+ INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
+ vec2_huffbits, 1, 1,
+ vec2_huffcodes, 2, 2, 562);
+
+ INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
+ vec1_huffbits, 1, 1,
+ vec1_huffcodes, 2, 2, 562);
+
+ /** calculate number of scale factor bands and their offsets
+ for every possible block size */
+ for (i = 0; i < num_possible_block_sizes; i++) {
+ int subframe_len = s->samples_per_frame >> i;
+ int x;
+ int band = 1;
+
+ s->sfb_offsets[i][0] = 0;
+
+ for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
+ int offset = (subframe_len * 2 * critical_freq[x])
+ / s->avctx->sample_rate + 2;
+ offset &= ~3;
+ if (offset > s->sfb_offsets[i][band - 1])
+ s->sfb_offsets[i][band++] = offset;
+ }
+ s->sfb_offsets[i][band - 1] = subframe_len;
+ s->num_sfb[i] = band - 1;
+ }
+
+
+ /** Scale factors can be shared between blocks of different size
+ as every block has a different scale factor band layout.
+ The matrix sf_offsets is needed to find the correct scale factor.
+ */
+
+ for (i = 0; i < num_possible_block_sizes; i++) {
+ int b;
+ for (b = 0; b < s->num_sfb[i]; b++) {
+ int x;
+ int offset = ((s->sfb_offsets[i][b]
+ + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
+ for (x = 0; x < num_possible_block_sizes; x++) {
+ int v = 0;
+ while (s->sfb_offsets[x][v + 1] << x < offset)
+ ++v;
+ s->sf_offsets[i][x][b] = v;
+ }
+ }
+ }
+
+ /** init MDCT, FIXME: only init needed sizes */
+ for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
+ ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
+ 1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
+ / (1 << (s->bits_per_sample - 1)));
+
+ /** init MDCT windows: simple sinus window */
+ for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
+ const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
+ ff_init_ff_sine_windows(win_idx);
+ s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
+ }
+
+ /** calculate subwoofer cutoff values */
+ for (i = 0; i < num_possible_block_sizes; i++) {
+ int block_size = s->samples_per_frame >> i;
+ int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
+ / s->avctx->sample_rate;
+ s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
+ }
+
+ /** calculate sine values for the decorrelation matrix */
+ for (i = 0; i < 33; i++)
+ sin64[i] = sin(i*M_PI / 64.0);
+
+ if (avctx->debug & FF_DEBUG_BITSTREAM)
+ dump_context(s);
+
+ avctx->channel_layout = channel_mask;
+
+ avcodec_get_frame_defaults(&s->frame);
+ avctx->coded_frame = &s->frame;
+
+ 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(WMAProDecodeCtx *s, int offset)
+{
+ int frame_len_shift = 0;
+ int subframe_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;
+
+ /** 1 bit indicates if the subframe is of maximum length */
+ if (s->max_subframe_len_bit) {
+ if (get_bits1(&s->gb))
+ frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
+ } else
+ frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
+
+ subframe_len = s->samples_per_frame >> frame_len_shift;
+
+ /** 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(WMAProDecodeCtx *s)
+{
+ uint16_t num_samples[WMAPRO_MAX_CHANNELS]; /**< sum of samples for all currently known subframes of a channel */
+ uint8_t contains_subframe[WMAPRO_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 subframe offsets and sizes */
+ int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
+ int c;
+
+ /* Should never consume more than 3073 bits (256 iterations for the
+ * while loop when always the minimum amount of 128 samples is substracted
+ * from missing samples in the 8 channel case).
+ * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
+ */
+
+ /** reset tiling information */
+ for (c = 0; c < s->num_channels; c++)
+ s->channel[c].num_subframes = 0;
+
+ memset(num_samples, 0, sizeof(num_samples));
+
+ if (s->max_num_subframes == 1 || get_bits1(&s->gb))
+ 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++) {
+ WMAProChannelCtx* 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 > samples_per_frame\n");
+ 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;
+ int offset = 0;
+ for (i = 0; i < s->channel[c].num_subframes; i++) {
+ av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
+ " len %i\n", s->frame_num, c, i,
+ s->channel[c].subframe_len[i]);
+ s->channel[c].subframe_offset[i] = offset;
+ offset += s->channel[c].subframe_len[i];
+ }
+ }
+
+ return 0;
+}
+
/**
*@brief Calculate a decorrelation matrix from the bitstream parameters.
*@param s codec context
*@param chgroup channel group for which the matrix needs to be calculated
*/
-static void decode_decorrelation_matrix(WMA3DecodeContext* s,
- WMA3ChannelGroup* chgroup)
+static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
+ WMAProChannelGrp *chgroup)
{
int i;
int offset = 0;
int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
- memset(chgroup->decorrelation_matrix,0,
- sizeof(float) *s->num_channels * s->num_channels);
+ memset(chgroup->decorrelation_matrix, 0, s->num_channels *
+ s->num_channels * sizeof(*chgroup->decorrelation_matrix));
- for (i=0;i<chgroup->num_channels * (chgroup->num_channels - 1) >> 1;i++)
- rotation_offset[i] = get_bits(&s->gb,6);
+ for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
+ rotation_offset[i] = get_bits(&s->gb, 6);
- for (i=0;i<chgroup->num_channels;i++)
+ for (i = 0; i < chgroup->num_channels; i++)
chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
- get_bits1(&s->gb) ? 1.0 : -1.0;
+ get_bits1(&s->gb) ? 1.0 : -1.0;
- for (i=1;i<chgroup->num_channels;i++) {
+ for (i = 1; i < chgroup->num_channels; i++) {
int x;
- for (x=0;x<i;x++) {
+ for (x = 0; x < i; x++) {
int y;
- for (y=0;y < i + 1 ; y++) {
+ for (y = 0; y < i + 1; y++) {
float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
int n = rotation_offset[offset + x];
float sinv;
float cosv;
- if (n<32) {
+ if (n < 32) {
sinv = sin64[n];
- cosv = sin64[32-n];
+ cosv = sin64[32 - n];
} else {
- sinv = sin64[64-n];
- cosv = -sin64[n-32];
+ sinv = sin64[64 - n];
+ cosv = -sin64[n - 32];
}
chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
}
/**
- *@brief Reconstruct the individual channel data.
+ *@brief Decode channel transformation parameters
*@param s codec context
+ *@return 0 in case of success, < 0 in case of bitstream errors
*/
-static void inverse_channel_transform(WMA3DecodeContext *s)
+static int decode_channel_transform(WMAProDecodeCtx* s)
{
int i;
+ /* should never consume more than 1921 bits for the 8 channel case
+ * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
+ * + MAX_CHANNELS + MAX_BANDS + 1)
+ */
- for (i=0;i<s->num_chgroups;i++) {
+ /** in the one channel case channel transforms are pointless */
+ s->num_chgroups = 0;
+ if (s->num_channels > 1) {
+ int remaining_channels = s->channels_for_cur_subframe;
- if (s->chgroup[i].transform == 1) {
- /** M/S stereo decoding */
- int16_t* sfb_offsets = s->cur_sfb_offsets;
- float* ch0 = *sfb_offsets + s->channel[0].coeffs;
- float* ch1 = *sfb_offsets++ + s->channel[1].coeffs;
- const char* tb = s->chgroup[i].transform_band;
- const char* tb_end = tb + s->num_bands;
+ if (get_bits1(&s->gb)) {
+ av_log_ask_for_sample(s->avctx,
+ "unsupported channel transform bit\n");
+ return AVERROR_INVALIDDATA;
+ }
- while (tb < tb_end) {
- const float* ch0_end = s->channel[0].coeffs +
- FFMIN(*sfb_offsets,s->subframe_len);
- if (*tb++ == 1) {
- while (ch0 < ch0_end) {
- const float v1 = *ch0;
- const float v2 = *ch1;
- *ch0++ = v1 - v2;
- *ch1++ = v1 + v2;
+ for (s->num_chgroups = 0; remaining_channels &&
+ s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
+ WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
+ float** channel_data = chgroup->channel_data;
+ chgroup->num_channels = 0;
+ chgroup->transform = 0;
+
+ /** decode channel mask */
+ if (remaining_channels > 2) {
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int channel_idx = s->channel_indexes_for_cur_subframe[i];
+ if (!s->channel[channel_idx].grouped
+ && get_bits1(&s->gb)) {
+ ++chgroup->num_channels;
+ s->channel[channel_idx].grouped = 1;
+ *channel_data++ = s->channel[channel_idx].coeffs;
+ }
+ }
+ } else {
+ chgroup->num_channels = remaining_channels;
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int channel_idx = s->channel_indexes_for_cur_subframe[i];
+ if (!s->channel[channel_idx].grouped)
+ *channel_data++ = s->channel[channel_idx].coeffs;
+ s->channel[channel_idx].grouped = 1;
+ }
+ }
+
+ /** decode transform type */
+ if (chgroup->num_channels == 2) {
+ if (get_bits1(&s->gb)) {
+ if (get_bits1(&s->gb)) {
+ av_log_ask_for_sample(s->avctx,
+ "unsupported channel transform type\n");
+ }
+ } else {
+ chgroup->transform = 1;
+ if (s->num_channels == 2) {
+ chgroup->decorrelation_matrix[0] = 1.0;
+ chgroup->decorrelation_matrix[1] = -1.0;
+ chgroup->decorrelation_matrix[2] = 1.0;
+ chgroup->decorrelation_matrix[3] = 1.0;
+ } else {
+ /** cos(pi/4) */
+ chgroup->decorrelation_matrix[0] = 0.70703125;
+ chgroup->decorrelation_matrix[1] = -0.70703125;
+ chgroup->decorrelation_matrix[2] = 0.70703125;
+ chgroup->decorrelation_matrix[3] = 0.70703125;
+ }
+ }
+ } else if (chgroup->num_channels > 2) {
+ if (get_bits1(&s->gb)) {
+ chgroup->transform = 1;
+ if (get_bits1(&s->gb)) {
+ decode_decorrelation_matrix(s, chgroup);
+ } else {
+ /** FIXME: more than 6 coupled channels not supported */
+ if (chgroup->num_channels > 6) {
+ av_log_ask_for_sample(s->avctx,
+ "coupled channels > 6\n");
+ } else {
+ memcpy(chgroup->decorrelation_matrix,
+ default_decorrelation[chgroup->num_channels],
+ chgroup->num_channels * chgroup->num_channels *
+ sizeof(*chgroup->decorrelation_matrix));
+ }
+ }
+ }
+ }
+
+ /** decode transform on / off */
+ if (chgroup->transform) {
+ if (!get_bits1(&s->gb)) {
+ int i;
+ /** transform can be enabled for individual bands */
+ for (i = 0; i < s->num_bands; i++) {
+ chgroup->transform_band[i] = get_bits1(&s->gb);
}
} else {
- while (ch0 < ch0_end) {
- *ch0++ *= 181.0 / 128;
- *ch1++ *= 181.0 / 128;
+ memset(chgroup->transform_band, 1, s->num_bands);
+ }
+ }
+ remaining_channels -= chgroup->num_channels;
+ }
+ }
+ return 0;
+}
+
+/**
+ *@brief Extract the coefficients from the bitstream.
+ *@param s codec context
+ *@param c current channel number
+ *@return 0 on success, < 0 in case of bitstream errors
+ */
+static int decode_coeffs(WMAProDecodeCtx *s, int c)
+{
+ /* Integers 0..15 as single-precision floats. The table saves a
+ costly int to float conversion, and storing the values as
+ integers allows fast sign-flipping. */
+ static const uint32_t fval_tab[16] = {
+ 0x00000000, 0x3f800000, 0x40000000, 0x40400000,
+ 0x40800000, 0x40a00000, 0x40c00000, 0x40e00000,
+ 0x41000000, 0x41100000, 0x41200000, 0x41300000,
+ 0x41400000, 0x41500000, 0x41600000, 0x41700000,
+ };
+ int vlctable;
+ VLC* vlc;
+ WMAProChannelCtx* ci = &s->channel[c];
+ int rl_mode = 0;
+ int cur_coeff = 0;
+ int num_zeros = 0;
+ const uint16_t* run;
+ const float* level;
+
+ av_dlog(s->avctx, "decode coefficients for channel %i\n", c);
+
+ vlctable = get_bits1(&s->gb);
+ vlc = &coef_vlc[vlctable];
+
+ if (vlctable) {
+ run = coef1_run;
+ level = coef1_level;
+ } else {
+ run = coef0_run;
+ level = coef0_level;
+ }
+
+ /** decode vector coefficients (consumes up to 167 bits per iteration for
+ 4 vector coded large values) */
+ while ((s->transmit_num_vec_coeffs || !rl_mode) &&
+ (cur_coeff + 3 < ci->num_vec_coeffs)) {
+ uint32_t vals[4];
+ int i;
+ unsigned int idx;
+
+ idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH);
+
+ if (idx == HUFF_VEC4_SIZE - 1) {
+ for (i = 0; i < 4; i += 2) {
+ idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH);
+ if (idx == HUFF_VEC2_SIZE - 1) {
+ uint32_t v0, v1;
+ v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
+ if (v0 == HUFF_VEC1_SIZE - 1)
+ v0 += ff_wma_get_large_val(&s->gb);
+ v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
+ if (v1 == HUFF_VEC1_SIZE - 1)
+ v1 += ff_wma_get_large_val(&s->gb);
+ vals[i ] = av_float2int(v0);
+ vals[i+1] = av_float2int(v1);
+ } else {
+ vals[i] = fval_tab[symbol_to_vec2[idx] >> 4 ];
+ vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF];
+ }
+ }
+ } else {
+ vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12 ];
+ vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF];
+ vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF];
+ vals[3] = fval_tab[ symbol_to_vec4[idx] & 0xF];
+ }
+
+ /** decode sign */
+ for (i = 0; i < 4; i++) {
+ if (vals[i]) {
+ uint32_t sign = get_bits1(&s->gb) - 1;
+ AV_WN32A(&ci->coeffs[cur_coeff], vals[i] ^ sign << 31);
+ num_zeros = 0;
+ } else {
+ ci->coeffs[cur_coeff] = 0;
+ /** switch to run level mode when subframe_len / 128 zeros
+ were found in a row */
+ rl_mode |= (++num_zeros > s->subframe_len >> 8);
+ }
+ ++cur_coeff;
+ }
+ }
+
+ /** decode run level coded coefficients */
+ if (cur_coeff < s->subframe_len) {
+ memset(&ci->coeffs[cur_coeff], 0,
+ sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
+ if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
+ level, run, 1, ci->coeffs,
+ cur_coeff, s->subframe_len,
+ s->subframe_len, s->esc_len, 0))
+ return AVERROR_INVALIDDATA;
+ }
+
+ return 0;
+}
+
+/**
+ *@brief Extract scale factors from the bitstream.
+ *@param s codec context
+ *@return 0 on success, < 0 in case of bitstream errors
+ */
+static int decode_scale_factors(WMAProDecodeCtx* s)
+{
+ int i;
+
+ /** should never consume more than 5344 bits
+ * MAX_CHANNELS * (1 + MAX_BANDS * 23)
+ */
+
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ int* sf;
+ int* sf_end;
+ s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx];
+ sf_end = s->channel[c].scale_factors + s->num_bands;
+
+ /** resample scale factors for the new block size
+ * as the scale factors might need to be resampled several times
+ * before some new values are transmitted, a backup of the last
+ * transmitted scale factors is kept in saved_scale_factors
+ */
+ if (s->channel[c].reuse_sf) {
+ const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
+ int b;
+ for (b = 0; b < s->num_bands; b++)
+ s->channel[c].scale_factors[b] =
+ s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++];
+ }
+
+ if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
+
+ if (!s->channel[c].reuse_sf) {
+ int val;
+ /** decode DPCM coded scale factors */
+ s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1;
+ val = 45 / s->channel[c].scale_factor_step;
+ for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
+ val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
+ *sf = val;
+ }
+ } else {
+ int i;
+ /** run level decode differences to the resampled factors */
+ for (i = 0; i < s->num_bands; i++) {
+ int idx;
+ int skip;
+ int val;
+ int sign;
+
+ idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH);
+
+ if (!idx) {
+ uint32_t code = get_bits(&s->gb, 14);
+ val = code >> 6;
+ sign = (code & 1) - 1;
+ skip = (code & 0x3f) >> 1;
+ } else if (idx == 1) {
+ break;
+ } else {
+ skip = scale_rl_run[idx];
+ val = scale_rl_level[idx];
+ sign = get_bits1(&s->gb)-1;
+ }
+
+ i += skip;
+ if (i >= s->num_bands) {
+ av_log(s->avctx, AV_LOG_ERROR,
+ "invalid scale factor coding\n");
+ return AVERROR_INVALIDDATA;
}
+ s->channel[c].scale_factors[i] += (val ^ sign) - sign;
}
- ++sfb_offsets;
}
- } else if (s->chgroup[i].transform) {
+ /** swap buffers */
+ s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx;
+ s->channel[c].table_idx = s->table_idx;
+ s->channel[c].reuse_sf = 1;
+ }
+
+ /** calculate new scale factor maximum */
+ s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
+ for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) {
+ s->channel[c].max_scale_factor =
+ FFMAX(s->channel[c].max_scale_factor, *sf);
+ }
+
+ }
+ return 0;
+}
+
+/**
+ *@brief Reconstruct the individual channel data.
+ *@param s codec context
+ */
+static void inverse_channel_transform(WMAProDecodeCtx *s)
+{
+ int i;
+
+ for (i = 0; i < s->num_chgroups; i++) {
+ if (s->chgroup[i].transform) {
float data[WMAPRO_MAX_CHANNELS];
const int num_channels = s->chgroup[i].num_channels;
float** ch_data = s->chgroup[i].channel_data;
int16_t* sfb;
/** multichannel decorrelation */
- for (sfb = s->cur_sfb_offsets ;
- sfb < s->cur_sfb_offsets + s->num_bands;sfb++) {
+ for (sfb = s->cur_sfb_offsets;
+ sfb < s->cur_sfb_offsets + s->num_bands; sfb++) {
+ int y;
if (*tb++ == 1) {
- int y;
/** multiply values with the decorrelation_matrix */
- for (y=sfb[0];y<FFMIN(sfb[1], s->subframe_len);y++) {
+ for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) {
const float* mat = s->chgroup[i].decorrelation_matrix;
- const float* data_end= data + num_channels;
- float* data_ptr= data;
+ const float* data_end = data + num_channels;
+ float* data_ptr = data;
float** ch;
- for (ch = ch_data;ch < ch_end; ch++)
- *data_ptr++ = (*ch)[y];
+ for (ch = ch_data; ch < ch_end; ch++)
+ *data_ptr++ = (*ch)[y];
for (ch = ch_data; ch < ch_end; ch++) {
float sum = 0;
(*ch)[y] = sum;
}
}
+ } else if (s->num_channels == 2) {
+ int len = FFMIN(sfb[1], s->subframe_len) - sfb[0];
+ s->dsp.vector_fmul_scalar(ch_data[0] + sfb[0],
+ ch_data[0] + sfb[0],
+ 181.0 / 128, len);
+ s->dsp.vector_fmul_scalar(ch_data[1] + sfb[0],
+ ch_data[1] + sfb[0],
+ 181.0 / 128, len);
}
}
}
}
}
+/**
+ *@brief Apply sine window and reconstruct the output buffer.
+ *@param s codec context
+ */
+static void wmapro_window(WMAProDecodeCtx *s)
+{
+ int i;
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ float* window;
+ int winlen = s->channel[c].prev_block_len;
+ float* start = s->channel[c].coeffs - (winlen >> 1);
+
+ if (s->subframe_len < winlen) {
+ start += (winlen - s->subframe_len) >> 1;
+ winlen = s->subframe_len;
+ }
+
+ window = s->windows[av_log2(winlen) - WMAPRO_BLOCK_MIN_BITS];
+
+ winlen >>= 1;
+
+ s->dsp.vector_fmul_window(start, start, start + winlen,
+ window, winlen);
+
+ s->channel[c].prev_block_len = s->subframe_len;
+ }
+}
+
+/**
+ *@brief Decode a single subframe (block).
+ *@param s codec context
+ *@return 0 on success, < 0 when decoding failed
+ */
+static int decode_subframe(WMAProDecodeCtx *s)
+{
+ int offset = s->samples_per_frame;
+ int subframe_len = s->samples_per_frame;
+ int i;
+ int total_samples = s->samples_per_frame * s->num_channels;
+ int transmit_coeffs = 0;
+ int cur_subwoofer_cutoff;
+
+ 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++) {
+ s->channel[i].grouped = 0;
+ 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];
+ }
+ }
+
+ av_dlog(s->avctx,
+ "processing subframe with offset %i len %i\n", offset, subframe_len);
+
+ /** 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;
+ /** substract 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;
+
+
+ av_dlog(s->avctx, "subframe is part of %i channels\n",
+ s->channels_for_cur_subframe);
+
+ /** calculate number of scale factor bands and their offsets */
+ s->table_idx = av_log2(s->samples_per_frame/subframe_len);
+ s->num_bands = s->num_sfb[s->table_idx];
+ s->cur_sfb_offsets = s->sfb_offsets[s->table_idx];
+ cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx];
+
+ /** configure the decoder for the current subframe */
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+
+ s->channel[c].coeffs = &s->channel[c].out[(s->samples_per_frame >> 1)
+ + offset];
+ }
+
+ s->subframe_len = subframe_len;
+ s->esc_len = av_log2(s->subframe_len - 1) + 1;
+
+ /** skip extended header if any */
+ if (get_bits1(&s->gb)) {
+ int num_fill_bits;
+ if (!(num_fill_bits = get_bits(&s->gb, 2))) {
+ int len = get_bits(&s->gb, 4);
+ num_fill_bits = get_bits(&s->gb, len) + 1;
+ }
+
+ if (num_fill_bits >= 0) {
+ if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
+ av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ skip_bits_long(&s->gb, num_fill_bits);
+ }
+ }
+
+ /** no idea for what the following bit is used */
+ if (get_bits1(&s->gb)) {
+ av_log_ask_for_sample(s->avctx, "reserved bit set\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+
+ if (decode_channel_transform(s) < 0)
+ return AVERROR_INVALIDDATA;
+
+
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
+ transmit_coeffs = 1;
+ }
+
+ if (transmit_coeffs) {
+ int step;
+ int quant_step = 90 * s->bits_per_sample >> 4;
+
+ /** decode number of vector coded coefficients */
+ if ((s->transmit_num_vec_coeffs = get_bits1(&s->gb))) {
+ int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ s->channel[c].num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
+ }
+ } else {
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ s->channel[c].num_vec_coeffs = s->subframe_len;
+ }
+ }
+ /** decode quantization step */
+ step = get_sbits(&s->gb, 6);
+ quant_step += step;
+ if (step == -32 || step == 31) {
+ const int sign = (step == 31) - 1;
+ int quant = 0;
+ while (get_bits_count(&s->gb) + 5 < s->num_saved_bits &&
+ (step = get_bits(&s->gb, 5)) == 31) {
+ quant += 31;
+ }
+ quant_step += ((quant + step) ^ sign) - sign;
+ }
+ if (quant_step < 0) {
+ av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
+ }
+
+ /** decode quantization step modifiers for every channel */
+
+ if (s->channels_for_cur_subframe == 1) {
+ s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
+ } else {
+ int modifier_len = get_bits(&s->gb, 3);
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ s->channel[c].quant_step = quant_step;
+ if (get_bits1(&s->gb)) {
+ if (modifier_len) {
+ s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
+ } else
+ ++s->channel[c].quant_step;
+ }
+ }
+ }
+
+ /** decode scale factors */
+ if (decode_scale_factors(s) < 0)
+ return AVERROR_INVALIDDATA;
+ }
+
+ av_dlog(s->avctx, "BITSTREAM: subframe header length was %i\n",
+ get_bits_count(&s->gb) - s->subframe_offset);
+
+ /** parse coefficients */
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ if (s->channel[c].transmit_coefs &&
+ get_bits_count(&s->gb) < s->num_saved_bits) {
+ decode_coeffs(s, c);
+ } else
+ memset(s->channel[c].coeffs, 0,
+ sizeof(*s->channel[c].coeffs) * subframe_len);
+ }
+
+ av_dlog(s->avctx, "BITSTREAM: subframe length was %i\n",
+ get_bits_count(&s->gb) - s->subframe_offset);
+
+ if (transmit_coeffs) {
+ FFTContext *mdct = &s->mdct_ctx[av_log2(subframe_len) - WMAPRO_BLOCK_MIN_BITS];
+ /** reconstruct the per channel data */
+ inverse_channel_transform(s);
+ for (i = 0; i < s->channels_for_cur_subframe; i++) {
+ int c = s->channel_indexes_for_cur_subframe[i];
+ const int* sf = s->channel[c].scale_factors;
+ int b;
+
+ if (c == s->lfe_channel)
+ memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) *
+ (subframe_len - cur_subwoofer_cutoff));
+
+ /** inverse quantization and rescaling */
+ for (b = 0; b < s->num_bands; b++) {
+ const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len);
+ const int exp = s->channel[c].quant_step -
+ (s->channel[c].max_scale_factor - *sf++) *
+ s->channel[c].scale_factor_step;
+ const float quant = pow(10.0, exp / 20.0);
+ int start = s->cur_sfb_offsets[b];
+ s->dsp.vector_fmul_scalar(s->tmp + start,
+ s->channel[c].coeffs + start,
+ quant, end - start);
+ }
+
+ /** apply imdct (imdct_half == DCTIV with reverse) */
+ mdct->imdct_half(mdct, s->channel[c].coeffs, s->tmp);
+ }
+ }
+
+ /** window and overlapp-add */
+ wmapro_window(s);
+
+ /** 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(WMAProDecodeCtx *s, int *got_frame_ptr)
+{
+ AVCodecContext *avctx = s->avctx;
+ GetBitContext* gb = &s->gb;
+ int more_frames = 0;
+ int len = 0;
+ int i, ret;
+ const float *out_ptr[WMAPRO_MAX_CHANNELS];
+ float *samples;
+
+ /** get frame length */
+ if (s->len_prefix)
+ len = get_bits(gb, s->log2_frame_size);
+
+ av_dlog(s->avctx, "decoding frame with length %x\n", len);
+
+ /** decode tile information */
+ if (decode_tilehdr(s)) {
+ s->packet_loss = 1;
+ return 0;
+ }
+
+ /** read postproc transform */
+ if (s->num_channels > 1 && get_bits1(gb)) {
+ if (get_bits1(gb)) {
+ for (i = 0; i < s->num_channels * s->num_channels; i++)
+ skip_bits(gb, 4);
+ }
+ }
+
+ /** read drc info */
+ if (s->dynamic_range_compression) {
+ s->drc_gain = get_bits(gb, 8);
+ av_dlog(s->avctx, "drc_gain %i\n", s->drc_gain);
+ }
+
+ /** 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 av_unused 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, "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, "end skip: %i\n", skip);
+ }
+
+ }
+
+ av_dlog(s->avctx, "BITSTREAM: frame header length was %i\n",
+ get_bits_count(gb) - s->frame_offset);
+
+ /** 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;
+ s->channel[i].reuse_sf = 0;
+ }
+
+ /** decode all subframes */
+ while (!s->parsed_all_subframes) {
+ if (decode_subframe(s) < 0) {
+ s->packet_loss = 1;
+ return 0;
+ }
+ }
+
+ /* get output buffer */
+ s->frame.nb_samples = s->samples_per_frame;
+ if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ s->packet_loss = 1;
+ return 0;
+ }
+ samples = (float *)s->frame.data[0];
+
+ /** interleave samples and write them to the output buffer */
+ for (i = 0; i < s->num_channels; i++)
+ out_ptr[i] = s->channel[i].out;
+ s->fmt_conv.float_interleave(samples, out_ptr, s->samples_per_frame,
+ s->num_channels);
+
+ for (i = 0; i < s->num_channels; i++) {
+ /** reuse second half of the IMDCT output for the next frame */
+ memcpy(&s->channel[i].out[0],
+ &s->channel[i].out[s->samples_per_frame],
+ s->samples_per_frame * sizeof(*s->channel[i].out) >> 1);
+ }
+
+ if (s->skip_frame) {
+ s->skip_frame = 0;
+ *got_frame_ptr = 0;
+ } else {
+ *got_frame_ptr = 1;
+ }
+
+ 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);
+ } else {
+ while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
+ }
+ }
+
+ /** 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(WMAProDecodeCtx *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(WMAProDecodeCtx *s, GetBitContext* gb, int len,
+ int append)
+{
+ int buflen;
+
+ /** when the frame data does not need to be concatenated, the input buffer
+ is resetted and additional bits from the previous frame are copyed
+ 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);
+
+ {
+ PutBitContext 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)
+{
+ WMAProDecodeCtx *s = avctx->priv_data;
+ GetBitContext* gb = &s->pgb;
+ const uint8_t* buf = avpkt->data;
+ int buf_size = avpkt->size;
+ int num_bits_prev_frame;
+ int packet_sequence_number;
+
+ *got_frame_ptr = 0;
+
+ 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);
+ skip_bits(gb, 2);
+
+ /** get number of bits that need to be added to the previous frame */
+ num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
+ av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
+ num_bits_prev_frame);
+
+ /** 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);
+ av_dlog(avctx, "accumulated %x bits of frame data\n",
+ s->num_saved_bits - s->frame_offset);
+
+ /** decode the cross packet frame if it is valid */
+ if (!s->packet_loss)
+ decode_frame(s, got_frame_ptr);
+ } else if (s->num_saved_bits - s->frame_offset) {
+ av_dlog(avctx, "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, got_frame_ptr);
+ } 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, got_frame_ptr);
+ } 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);
+ }
+
+ s->packet_offset = get_bits_count(gb) & 7;
+ if (s->packet_loss)
+ return AVERROR_INVALIDDATA;
+
+ if (*got_frame_ptr)
+ *(AVFrame *)data = s->frame;
+
+ return get_bits_count(gb) >> 3;
+}
+
+/**
+ *@brief Clear decoder buffers (for seeking).
+ *@param avctx codec context
+ */
+static void flush(AVCodecContext *avctx)
+{
+ WMAProDecodeCtx *s = avctx->priv_data;
+ int i;
+ /** reset output buffer as a part of it is used during the windowing of a
+ new frame */
+ for (i = 0; i < s->num_channels; i++)
+ memset(s->channel[i].out, 0, s->samples_per_frame *
+ sizeof(*s->channel[i].out));
+ s->packet_loss = 1;
+}
+
+
+/**
+ *@brief wmapro decoder
+ */
+AVCodec ff_wmapro_decoder = {
+ .name = "wmapro",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = CODEC_ID_WMAPRO,
+ .priv_data_size = sizeof(WMAProDecodeCtx),
+ .init = decode_init,
+ .close = decode_end,
+ .decode = decode_packet,
+ .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
+ .flush= flush,
+ .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
+};
projects / ffmpeg / blobdiff