57 #define ALAC_EXTRADATA_SIZE 36
106 int sign_modifier = 0;
113 k =
av_log2((history >> 9) + 3);
118 output_buffer[i] = (x >> 1) ^ -(x & 1);
124 history += x * rice_history_mult -
125 ((history * rice_history_mult) >> 9);
128 if ((history < 128) && (i + 1 < nb_samples)) {
132 k = 7 -
av_log2(history) + ((history + 16) >> 6);
136 if (block_size > 0) {
137 if (block_size >= nb_samples - i) {
139 "invalid zero block size of %d %d %d\n", block_size,
141 block_size = nb_samples - i - 1;
143 memset(&output_buffer[i + 1], 0,
144 block_size *
sizeof(*output_buffer));
147 if (block_size <= 0xffff)
161 int lpc_order,
int lpc_quant)
167 *buffer_out = *error_buffer;
173 memcpy(&buffer_out[1], &error_buffer[1],
174 (nb_samples - 1) *
sizeof(*buffer_out));
178 if (lpc_order == 31) {
181 buffer_out[i] =
sign_extend(buffer_out[i - 1] + error_buffer[i],
188 for (i = 1; i <= lpc_order; i++)
189 buffer_out[i] =
sign_extend(buffer_out[i - 1] + error_buffer[i], bps);
196 int error_val = error_buffer[i];
201 for (j = 0; j < lpc_order; j++)
202 val += (pred[j] - d) * lpc_coefs[j];
203 val = (val + (1 << (lpc_quant - 1))) >> lpc_quant;
204 val += d + error_val;
210 for (j = 0; j < lpc_order && error_val * error_sign > 0; j++) {
214 lpc_coefs[j] -= sign;
216 error_val -= (val >> lpc_quant) * (j + 1);
223 int decorr_shift,
int decorr_left_weight)
233 a -= (b * decorr_left_weight) >> decorr_shift;
246 for (ch = 0; ch < channels; ch++)
248 buffer[ch][i] = (buffer[ch][i] << extra_bits) | extra_bits_buffer[ch][i];
255 int has_size,
bps, is_compressed, decorr_shift, decorr_left_weight, ret;
256 uint32_t output_samples;
291 }
else if (output_samples != alac->
nb_samples) {
298 for (ch = 0; ch < channels; ch++)
303 int16_t lpc_coefs[2][32];
305 int prediction_type[2];
307 int rice_history_mult[2];
312 for (ch = 0; ch < channels; ch++) {
315 rice_history_mult[ch] =
get_bits(&alac->
gb, 3);
322 for (i = lpc_order[ch] - 1; i >= 0; i--)
328 for (ch = 0; ch < channels; ch++)
332 for (ch = 0; ch < channels; ch++) {
338 if (prediction_type[ch] == 15) {
349 }
else if (prediction_type[ch] > 0) {
351 prediction_type[ch]);
355 bps, lpc_coefs[ch], lpc_order[ch], lpc_quant[ch]);
360 for (ch = 0; ch < channels; ch++) {
367 decorr_left_weight = 0;
370 if (channels == 2 && decorr_left_weight) {
372 decorr_shift, decorr_left_weight);
382 for (ch = 0; ch < channels; ch++) {
389 for (ch = 0; ch < channels; ch++) {
400 int *got_frame_ptr,
AVPacket *avpkt)
405 int ch, ret, got_end;
423 channels = (element ==
TYPE_CPE) ? 2 : 1;
424 if (ch + channels > alac->
channels ||
476 buf_size, buf_alloc_fail);
480 buf_size, buf_alloc_fail);
484 buf_size, buf_alloc_fail);
512 alac->
rice_limit = bytestream2_get_byteu(&gb);
513 alac->
channels = bytestream2_get_byteu(&gb);
514 bytestream2_get_be16u(&gb);
515 bytestream2_get_be32u(&gb);
516 bytestream2_get_be32u(&gb);
517 bytestream2_get_be32u(&gb);
int nb_samples
number of samples in the current frame
This structure describes decoded (raw) audio or video data.
#define ALAC_EXTRADATA_SIZE
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
AVFrame * coded_frame
the picture in the bitstream
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
int32_t * extra_bits_buffer[2]
static int get_sbits(GetBitContext *s, int n)
static int get_sbits_long(GetBitContext *s, int n)
Read 0-32 bits as a signed integer.
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
int32_t * predict_error_buffer[2]
static int get_unary_0_9(GetBitContext *gb)
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
enum AVSampleFormat sample_fmt
audio sample format
uint8_t rice_initial_history
static av_cold int alac_decode_close(AVCodecContext *avctx)
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
static int get_bits_count(const GetBitContext *s)
static av_always_inline void bytestream2_skipu(GetByteContext *g, unsigned int size)
bitstream reader API header.
int32_t * output_samples_buffer[2]
static int alac_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
int extra_bits
number of extra bits beyond 16-bit
static int init(AVCodecParserContext *s)
static int get_bits_left(GetBitContext *gb)
static void append_extra_bits(int32_t *buffer[2], int32_t *extra_bits_buffer[2], int extra_bits, int channels, int nb_samples)
static void lpc_prediction(int32_t *error_buffer, int32_t *buffer_out, int nb_samples, int bps, int16_t *lpc_coefs, int lpc_order, int lpc_quant)
void av_log_ask_for_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message asking for a sample.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
static int sign_only(int v)
void av_log(void *avcl, int level, const char *fmt,...)
const char * name
Name of the codec implementation.
uint64_t channel_layout
Audio channel layout.
#define ALAC_MAX_CHANNELS
uint32_t max_samples_per_frame
static void output_buffer(int16_t **samples, int nchan, int blocksize, int32_t **buffer)
static void decorrelate_stereo(int32_t *buffer[2], int nb_samples, int decorr_shift, int decorr_left_weight)
audio channel layout utility functions
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame)
Get a buffer for a frame.
static unsigned int show_bits(GetBitContext *s, int n)
Show 1-25 bits.
static int alac_set_info(ALACContext *alac)
uint8_t rice_history_mult
const uint64_t ff_alac_channel_layouts[ALAC_MAX_CHANNELS+1]
static const float pred[4]
main external API structure.
static void close(AVCodecParserContext *s)
static unsigned int get_bits1(GetBitContext *s)
void avcodec_get_frame_defaults(AVFrame *frame)
Set the fields of the given AVFrame to default values.
static void skip_bits(GetBitContext *s, int n)
static void rice_decompress(ALACContext *alac, int32_t *output_buffer, int nb_samples, int bps, int rice_history_mult)
static unsigned int decode_scalar(GetBitContext *gb, int k, int bps)
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
const uint8_t ff_alac_channel_layout_offsets[ALAC_MAX_CHANNELS][ALAC_MAX_CHANNELS]
static av_const int sign_extend(int val, unsigned bits)
common internal api header.
static av_cold int alac_decode_init(AVCodecContext *avctx)
#define FF_ALLOC_OR_GOTO(ctx, p, size, label)
#define AVERROR_INVALIDDATA
#define AVERROR_PATCHWELCOME
static int allocate_buffers(ALACContext *alac)
int channels
number of audio channels
uint8_t ** extended_data
pointers to the data planes/channels.
This structure stores compressed data.
int nb_samples
number of audio samples (per channel) described by this frame
static int decode_element(AVCodecContext *avctx, void *data, int ch_index, int channels)