Libav
vorbis.c
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1 /*
2  * This file is part of Libav.
3  *
4  * Libav is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * Libav is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with Libav; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
25 #define BITSTREAM_READER_LE
26 #include "avcodec.h"
27 #include "get_bits.h"
28 
29 #include "vorbis.h"
30 
31 
32 /* Helper functions */
33 
34 // x^(1/n)
35 unsigned int ff_vorbis_nth_root(unsigned int x, unsigned int n)
36 {
37  unsigned int ret = 0, i, j;
38 
39  do {
40  ++ret;
41  for (i = 0, j = ret; i < n - 1; i++)
42  j *= ret;
43  } while (j <= x);
44 
45  return ret - 1;
46 }
47 
48 // Generate vlc codes from vorbis huffman code lengths
49 
50 // the two bits[p] > 32 checks should be redundant, all calling code should
51 // already ensure that, but since it allows overwriting the stack it seems
52 // reasonable to check redundantly.
53 int ff_vorbis_len2vlc(uint8_t *bits, uint32_t *codes, unsigned num)
54 {
55  uint32_t exit_at_level[33] = { 404 };
56 
57  unsigned i, j, p, code;
58 
59 #ifdef DEBUG
60  GetBitContext gb;
61 #endif
62 
63  for (p = 0; (bits[p] == 0) && (p < num); ++p)
64  ;
65  if (p == num)
66  return 0;
67 
68  codes[p] = 0;
69  if (bits[p] > 32)
70  return 1;
71  for (i = 0; i < bits[p]; ++i)
72  exit_at_level[i+1] = 1 << i;
73 
74 #ifdef DEBUG
75  av_log(NULL, AV_LOG_INFO, " %u. of %u code len %d code %d - ", p, num, bits[p], codes[p]);
76  init_get_bits(&gb, (uint8_t *)&codes[p], bits[p]);
77  for (i = 0; i < bits[p]; ++i)
78  av_log(NULL, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
79  av_log(NULL, AV_LOG_INFO, "\n");
80 #endif
81 
82  ++p;
83 
84  for (; p < num; ++p) {
85  if (bits[p] > 32)
86  return 1;
87  if (bits[p] == 0)
88  continue;
89  // find corresponding exit(node which the tree can grow further from)
90  for (i = bits[p]; i > 0; --i)
91  if (exit_at_level[i])
92  break;
93  if (!i) // overspecified tree
94  return 1;
95  code = exit_at_level[i];
96  exit_at_level[i] = 0;
97  // construct code (append 0s to end) and introduce new exits
98  for (j = i + 1 ;j <= bits[p]; ++j)
99  exit_at_level[j] = code + (1 << (j - 1));
100  codes[p] = code;
101 
102 #ifdef DEBUG
103  av_log(NULL, AV_LOG_INFO, " %d. code len %d code %d - ", p, bits[p], codes[p]);
104  init_get_bits(&gb, (uint8_t *)&codes[p], bits[p]);
105  for (i = 0; i < bits[p]; ++i)
106  av_log(NULL, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
107  av_log(NULL, AV_LOG_INFO, "\n");
108 #endif
109 
110  }
111 
112  //no exits should be left (underspecified tree - ie. unused valid vlcs - not allowed by SPEC)
113  for (p = 1; p < 33; p++)
114  if (exit_at_level[p])
115  return 1;
116 
117  return 0;
118 }
119 
121  vorbis_floor1_entry *list, int values)
122 {
123  int i;
124  list[0].sort = 0;
125  list[1].sort = 1;
126  for (i = 2; i < values; i++) {
127  int j;
128  list[i].low = 0;
129  list[i].high = 1;
130  list[i].sort = i;
131  for (j = 2; j < i; j++) {
132  int tmp = list[j].x;
133  if (tmp < list[i].x) {
134  if (tmp > list[list[i].low].x)
135  list[i].low = j;
136  } else {
137  if (tmp < list[list[i].high].x)
138  list[i].high = j;
139  }
140  }
141  }
142  for (i = 0; i < values - 1; i++) {
143  int j;
144  for (j = i + 1; j < values; j++) {
145  if (list[i].x == list[j].x) {
146  av_log(avctx, AV_LOG_ERROR,
147  "Duplicate value found in floor 1 X coordinates\n");
148  return AVERROR_INVALIDDATA;
149  }
150  if (list[list[i].sort].x > list[list[j].sort].x) {
151  int tmp = list[i].sort;
152  list[i].sort = list[j].sort;
153  list[j].sort = tmp;
154  }
155  }
156  }
157  return 0;
158 }
159 
160 static inline void render_line_unrolled(intptr_t x, int y, int x1,
161  intptr_t sy, int ady, int adx,
162  float *buf)
163 {
164  int err = -adx;
165  x -= x1 - 1;
166  buf += x1 - 1;
167  while (++x < 0) {
168  err += ady;
169  if (err >= 0) {
170  err += ady - adx;
171  y += sy;
172  buf[x++] = ff_vorbis_floor1_inverse_db_table[av_clip_uint8(y)];
173  }
174  buf[x] = ff_vorbis_floor1_inverse_db_table[av_clip_uint8(y)];
175  }
176  if (x <= 0) {
177  if (err + ady >= 0)
178  y += sy;
179  buf[x] = ff_vorbis_floor1_inverse_db_table[av_clip_uint8(y)];
180  }
181 }
182 
183 static void render_line(int x0, int y0, int x1, int y1, float *buf)
184 {
185  int dy = y1 - y0;
186  int adx = x1 - x0;
187  int ady = FFABS(dy);
188  int sy = dy < 0 ? -1 : 1;
189  buf[x0] = ff_vorbis_floor1_inverse_db_table[av_clip_uint8(y0)];
190  if (ady*2 <= adx) { // optimized common case
191  render_line_unrolled(x0, y0, x1, sy, ady, adx, buf);
192  } else {
193  int base = dy / adx;
194  int x = x0;
195  int y = y0;
196  int err = -adx;
197  ady -= FFABS(base) * adx;
198  while (++x < x1) {
199  y += base;
200  err += ady;
201  if (err >= 0) {
202  err -= adx;
203  y += sy;
204  }
205  buf[x] = ff_vorbis_floor1_inverse_db_table[av_clip_uint8(y)];
206  }
207  }
208 }
209 
211  uint16_t *y_list, int *flag,
212  int multiplier, float *out, int samples)
213 {
214  int lx, ly, i;
215  lx = 0;
216  ly = y_list[0] * multiplier;
217  for (i = 1; i < values; i++) {
218  int pos = list[i].sort;
219  if (flag[pos]) {
220  int x1 = list[pos].x;
221  int y1 = y_list[pos] * multiplier;
222  if (lx < samples)
223  render_line(lx, ly, FFMIN(x1,samples), y1, out);
224  lx = x1;
225  ly = y1;
226  }
227  if (lx >= samples)
228  break;
229  }
230  if (lx < samples)
231  render_line(lx, ly, samples, ly, out);
232 }
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
unsigned int ff_vorbis_nth_root(unsigned int x, unsigned int n)
Definition: vorbis.c:35
const float ff_vorbis_floor1_inverse_db_table[256]
Definition: vorbis_data.c:2123
uint16_t sort
Definition: vorbis.h:34
uint8_t bits
Definition: crc.c:251
uint8_t
static void render_line(int x0, int y0, int x1, int y1, float *buf)
Definition: vorbis.c:183
bitstream reader API header.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
uint16_t x
Definition: vorbis.h:33
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
#define FFMIN(a, b)
Definition: common.h:57
int ff_vorbis_len2vlc(uint8_t *bits, uint32_t *codes, unsigned num)
Definition: vorbis.c:53
#define FFABS(a)
Definition: common.h:52
NULL
Definition: eval.c:55
#define AV_LOG_INFO
Standard information.
Definition: log.h:134
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1050
uint16_t low
Definition: vorbis.h:35
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:271
uint16_t high
Definition: vorbis.h:36
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:375
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_dlog(ac->avr,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> out
static void render_line_unrolled(intptr_t x, int y, int x1, intptr_t sy, int ady, int adx, float *buf)
Definition: vorbis.c:160
void ff_vorbis_floor1_render_list(vorbis_floor1_entry *list, int values, uint16_t *y_list, int *flag, int multiplier, float *out, int samples)
Definition: vorbis.c:210
Definition: vorbis.h:32
int ff_vorbis_ready_floor1_list(AVCodecContext *avctx, vorbis_floor1_entry *list, int values)
Definition: vorbis.c:120