53 0, 1, 2, 3, 4, 5, 6, 7,
54 8, 9, 10, 11, 12, 13, 14, 16,
55 17, 19, 21, 23, 25, 28, 31, 34,
56 37, 41, 45, 50, 55, 60, 66, 73,
57 80, 88, 97, 107, 118, 130, 143, 157,
58 173, 190, 209, 230, 253, 279, 307, 337,
59 371, 408, 449, 494, 544, 598, 658, 724,
60 796, 876, 963, 1060, 1166, 1282, 1411, 1552,
61 1707, 1878, 2066, 2272, 2499, 2749, 3024, 3327,
62 3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132,
63 7845, 8630, 9493, 10442, 11487, 12635, 13899, 15289,
64 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767,
68 0, 1, 2, 3, 4, 5, 6, 7,
69 8, 9, 10, 11, 12, 13, 14, 15,
70 16, 17, 18, 19, 20, 21, 22, 23,
71 24, 25, 26, 27, 28, 29, 30, 31,
72 32, 33, 34, 35, 36, 37, 38, 39,
73 40, 41, 42, 43, 47, 51, 56, 61,
74 66, 72, 79, 86, 94, 102, 112, 122,
75 133, 145, 158, 173, 189, 206, 225, 245,
76 267, 292, 318, 348, 379, 414, 452, 493,
77 538, 587, 640, 699, 763, 832, 908, 991,
78 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993,
79 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008,
80 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059,
81 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206,
82 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589,
83 -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1,
84 1, 1, 5481, 10503, 15105, 19322, 23186, 26728,
85 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298,
86 -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597,
87 -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772,
88 -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373,
89 -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180,
90 -1081, -991, -908, -832, -763, -699, -640, -587,
91 -538, -493, -452, -414, -379, -348, -318, -292,
92 -267, -245, -225, -206, -189, -173, -158, -145,
93 -133, -122, -112, -102, -94, -86, -79, -72,
94 -66, -61, -56, -51, -47, -43, -42, -41,
95 -40, -39, -38, -37, -36, -35, -34, -33,
96 -32, -31, -30, -29, -28, -27, -26, -25,
97 -24, -23, -22, -21, -20, -19, -18, -17,
98 -16, -15, -14, -13, -12, -11, -10, -9,
99 -8, -7, -6, -5, -4, -3, -2, -1
104 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
105 -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0
109 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
110 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15
114 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
115 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
116 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
117 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
118 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
119 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
120 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
121 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
122 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
123 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
124 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
125 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
126 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
146 for (i = 0; i < 128; i++) {
172 for (i = -128; i < 128; i++) {
173 int16_t
square = i * i * 2;
184 for (i = 0; i < 127; i++) {
185 delta += (code >> 5);
192 s->
array[255] = delta + (code >> 5);
210 int *got_frame_ptr,
AVPacket *avpkt)
212 int buf_size = avpkt->
size;
219 int16_t *output_samples, *samples_end;
222 if (stereo && (buf_size & 1))
232 out = buf_size - 6 - avctx->
channels;
235 out = buf_size - 2 * avctx->
channels;
261 output_samples = (int16_t *)frame->
data[0];
262 samples_end = output_samples + out;
270 predictor[1] =
sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
271 predictor[0] =
sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
273 predictor[0] =
sign_extend(bytestream2_get_le16u(&gb), 16);
277 while (output_samples < samples_end) {
278 predictor[ch] += s->
array[bytestream2_get_byteu(&gb)];
280 *output_samples++ = predictor[ch];
290 for (ch = 0; ch < avctx->
channels; ch++) {
291 predictor[ch] =
sign_extend(bytestream2_get_le16u(&gb), 16);
292 *output_samples++ = predictor[ch];
296 while (output_samples < samples_end) {
299 *output_samples++ = predictor[ch];
308 int shift[2] = { 4, 4 };
310 for (ch = 0; ch < avctx->
channels; ch++)
311 predictor[ch] =
sign_extend(bytestream2_get_le16u(&gb), 16);
314 while (output_samples < samples_end) {
315 int diff = bytestream2_get_byteu(&gb);
321 shift[ch] -= (2 * n);
328 predictor[ch] +=
diff;
331 *output_samples++ = predictor[ch];
341 *samples_end_u8 = output_samples_u8 +
out;
342 while (output_samples_u8 < samples_end_u8) {
343 int n = bytestream2_get_byteu(&gb);
347 *output_samples_u8++ = s->
sample[0];
351 *output_samples_u8++ = s->
sample[stereo];
354 while (output_samples < samples_end) {
355 int n = bytestream2_get_byteu(&gb);
359 *output_samples++ = s->
sample[ch];
367 while (output_samples < samples_end) {
368 int8_t n = bytestream2_get_byteu(&gb);
374 *output_samples++ = s->
sample[ch];
382 while (output_samples < samples_end) {
383 uint8_t n = bytestream2_get_byteu(&gb);
385 *output_samples++ = s->
sample[idx] += (unsigned)s->
array[n];
394 while (output_samples < samples_end) {
395 uint8_t n = bytestream2_get_byteu(&gb);
400 *output_samples++ = s->
sample[idx];
412 #define DPCM_DECODER(id_, name_, long_name_) \ 413 AVCodec ff_ ## name_ ## _decoder = { \ 415 .long_name = NULL_IF_CONFIG_SMALL(long_name_), \ 416 .type = AVMEDIA_TYPE_AUDIO, \ 418 .priv_data_size = sizeof(DPCMContext), \ 419 .init = dpcm_decode_init, \ 420 .decode = dpcm_decode_frame, \ 421 .capabilities = AV_CODEC_CAP_DR1, \ const struct AVCodec * codec
static int shift(int a, int b)
This structure describes decoded (raw) audio or video data.
ptrdiff_t const GLvoid * data
static const int8_t sol_table_old[16]
#define AV_LOG_WARNING
Something somehow does not look correct.
const int8_t * sol_table
delta table for SOL_DPCM
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
enum AVSampleFormat sample_fmt
audio sample format
static const int16_t interplay_delta_table[]
static av_always_inline void bytestream2_skipu(GetByteContext *g, unsigned int size)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
static const int8_t sol_table_new[16]
static int dpcm_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
static void predictor(uint8_t *src, ptrdiff_t size)
static const int32_t derf_steps[96]
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Libavcodec external API header.
static const int16_t sol_table_16[128]
main external API structure.
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
static av_const int sign_extend(int val, unsigned bits)
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
#define DPCM_DECODER(id_, name_, long_name_)
common internal api header.
static av_cold int dpcm_decode_init(AVCodecContext *avctx)
static av_always_inline int diff(const uint32_t a, const uint32_t b)
int channels
number of audio channels
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
int sample[2]
previous sample (for SOL_DPCM)
int nb_samples
number of audio samples (per channel) described by this frame
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about which is also called distortion Distortion can be quantified by almost any quality measurement one chooses the sum of squared differences is used but more complex methods that consider psychovisual effects can be used as well It makes no difference in this discussion First step