git.sesse.net Git - ffmpeg/blob - libavfilter/formats.c

   1 /*
   2  * Filter layer - format negotiation
   3  * Copyright (c) 2007 Bobby Bingham
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavutil/avassert.h"
  23 #include "libavutil/channel_layout.h"
  24 #include "libavutil/common.h"
  25 #include "libavutil/eval.h"
  26 #include "libavutil/pixdesc.h"
  27 #include "libavutil/parseutils.h"
  28 #include "avfilter.h"
  29 #include "internal.h"
  30 #include "formats.h"
  31
  32 #define KNOWN(l) (!FF_LAYOUT2COUNT(l)) /* for readability */
  33
  34 /**
  35  * Add all refs from a to ret and destroy a.
  36  */
  37 #define MERGE_REF(ret, a, fmts, type, fail)                                \
  38 do {                                                                       \
  39     type ***tmp;                                                           \
  40     int i;                                                                 \
  41                                                                            \
  42     if (!(tmp = av_realloc_array(ret->refs, ret->refcount + a->refcount,   \
  43                                  sizeof(*tmp))))                           \
  44         goto fail;                                                         \
  45     ret->refs = tmp;                                                       \
  46                                                                            \
  47     for (i = 0; i < a->refcount; i ++) {                                   \
  48         ret->refs[ret->refcount] = a->refs[i];                             \
  49         *ret->refs[ret->refcount++] = ret;                                 \
  50     }                                                                      \
  51                                                                            \
  52     av_freep(&a->refs);                                                    \
  53     av_freep(&a->fmts);                                                    \
  54     av_freep(&a);                                                          \
  55 } while (0)
  56
  57 /**
  58  * Add all formats common for a and b to ret, copy the refs and destroy
  59  * a and b.
  60  */
  61 #define MERGE_FORMATS(ret, a, b, fmts, nb, type, fail)                          \
  62 do {                                                                            \
  63     int i, j, k = 0, count = FFMIN(a->nb, b->nb);                               \
  64                                                                                 \
  65     if (!(ret = av_mallocz(sizeof(*ret))))                                      \
  66         goto fail;                                                              \
  67                                                                                 \
  68     if (count) {                                                                \
  69         if (!(ret->fmts = av_malloc_array(count, sizeof(*ret->fmts))))          \
  70             goto fail;                                                          \
  71         for (i = 0; i < a->nb; i++)                                             \
  72             for (j = 0; j < b->nb; j++)                                         \
  73                 if (a->fmts[i] == b->fmts[j]) {                                 \
  74                     if(k >= FFMIN(a->nb, b->nb)){                               \
  75                         av_log(NULL, AV_LOG_ERROR, "Duplicate formats in avfilter_merge_formats() detected\n"); \
  76                         av_free(ret->fmts);                                     \
  77                         av_free(ret);                                           \
  78                         return NULL;                                            \
  79                     }                                                           \
  80                     ret->fmts[k++] = a->fmts[i];                                \
  81                 }                                                               \
  82     }                                                                           \
  83     ret->nb = k;                                                                \
  84     /* check that there was at least one common format */                       \
  85     if (!ret->nb)                                                               \
  86         goto fail;                                                              \
  87                                                                                 \
  88     MERGE_REF(ret, a, fmts, type, fail);                                        \
  89     MERGE_REF(ret, b, fmts, type, fail);                                        \
  90 } while (0)
  91
  92 AVFilterFormats *ff_merge_formats(AVFilterFormats *a, AVFilterFormats *b,
  93                                   enum AVMediaType type)
  94 {
  95     AVFilterFormats *ret = NULL;
  96     int i, j;
  97     int alpha1=0, alpha2=0;
  98     int chroma1=0, chroma2=0;
  99
 100     if (a == b)
 101         return a;
 102
 103     /* Do not lose chroma or alpha in merging.
 104        It happens if both lists have formats with chroma (resp. alpha), but
 105        the only formats in common do not have it (e.g. YUV+gray vs.
 106        RGB+gray): in that case, the merging would select the gray format,
 107        possibly causing a lossy conversion elsewhere in the graph.
 108        To avoid that, pretend that there are no common formats to force the
 109        insertion of a conversion filter. */
 110     if (type == AVMEDIA_TYPE_VIDEO)
 111         for (i = 0; i < a->nb_formats; i++)
 112             for (j = 0; j < b->nb_formats; j++) {
 113                 const AVPixFmtDescriptor *adesc = av_pix_fmt_desc_get(a->formats[i]);
 114                 const AVPixFmtDescriptor *bdesc = av_pix_fmt_desc_get(b->formats[j]);
 115                 alpha2 |= adesc->flags & bdesc->flags & AV_PIX_FMT_FLAG_ALPHA;
 116                 chroma2|= adesc->nb_components > 1 && bdesc->nb_components > 1;
 117                 if (a->formats[i] == b->formats[j]) {
 118                     alpha1 |= adesc->flags & AV_PIX_FMT_FLAG_ALPHA;
 119                     chroma1|= adesc->nb_components > 1;
 120                 }
 121             }
 122
 123     // If chroma or alpha can be lost through merging then do not merge
 124     if (alpha2 > alpha1 || chroma2 > chroma1)
 125         return NULL;
 126
 127     MERGE_FORMATS(ret, a, b, formats, nb_formats, AVFilterFormats, fail);
 128
 129     return ret;
 130 fail:
 131     if (ret) {
 132         av_freep(&ret->refs);
 133         av_freep(&ret->formats);
 134     }
 135     av_freep(&ret);
 136     return NULL;
 137 }
 138
 139 AVFilterFormats *ff_merge_samplerates(AVFilterFormats *a,
 140                                       AVFilterFormats *b)
 141 {
 142     AVFilterFormats *ret = NULL;
 143
 144     if (a == b) return a;
 145
 146     if (a->nb_formats && b->nb_formats) {
 147         MERGE_FORMATS(ret, a, b, formats, nb_formats, AVFilterFormats, fail);
 148     } else if (a->nb_formats) {
 149         MERGE_REF(a, b, formats, AVFilterFormats, fail);
 150         ret = a;
 151     } else {
 152         MERGE_REF(b, a, formats, AVFilterFormats, fail);
 153         ret = b;
 154     }
 155
 156     return ret;
 157 fail:
 158     if (ret) {
 159         av_freep(&ret->refs);
 160         av_freep(&ret->formats);
 161     }
 162     av_freep(&ret);
 163     return NULL;
 164 }
 165
 166 AVFilterChannelLayouts *ff_merge_channel_layouts(AVFilterChannelLayouts *a,
 167                                                  AVFilterChannelLayouts *b)
 168 {
 169     AVFilterChannelLayouts *ret = NULL;
 170     unsigned a_all = a->all_layouts + a->all_counts;
 171     unsigned b_all = b->all_layouts + b->all_counts;
 172     int ret_max, ret_nb = 0, i, j, round;
 173
 174     if (a == b) return a;
 175
 176     /* Put the most generic set in a, to avoid doing everything twice */
 177     if (a_all < b_all) {
 178         FFSWAP(AVFilterChannelLayouts *, a, b);
 179         FFSWAP(unsigned, a_all, b_all);
 180     }
 181     if (a_all) {
 182         if (a_all == 1 && !b_all) {
 183             /* keep only known layouts in b; works also for b_all = 1 */
 184             for (i = j = 0; i < b->nb_channel_layouts; i++)
 185                 if (KNOWN(b->channel_layouts[i]))
 186                     b->channel_layouts[j++] = b->channel_layouts[i];
 187             /* Not optimal: the unknown layouts of b may become known after
 188                another merge. */
 189             if (!j)
 190                 return NULL;
 191             b->nb_channel_layouts = j;
 192         }
 193         MERGE_REF(b, a, channel_layouts, AVFilterChannelLayouts, fail);
 194         return b;
 195     }
 196
 197     ret_max = a->nb_channel_layouts + b->nb_channel_layouts;
 198     if (!(ret = av_mallocz(sizeof(*ret))) ||
 199         !(ret->channel_layouts = av_malloc_array(ret_max,
 200                                                  sizeof(*ret->channel_layouts))))
 201         goto fail;
 202
 203     /* a[known] intersect b[known] */
 204     for (i = 0; i < a->nb_channel_layouts; i++) {
 205         if (!KNOWN(a->channel_layouts[i]))
 206             continue;
 207         for (j = 0; j < b->nb_channel_layouts; j++) {
 208             if (a->channel_layouts[i] == b->channel_layouts[j]) {
 209                 ret->channel_layouts[ret_nb++] = a->channel_layouts[i];
 210                 a->channel_layouts[i] = b->channel_layouts[j] = 0;
 211             }
 212         }
 213     }
 214     /* 1st round: a[known] intersect b[generic]
 215        2nd round: a[generic] intersect b[known] */
 216     for (round = 0; round < 2; round++) {
 217         for (i = 0; i < a->nb_channel_layouts; i++) {
 218             uint64_t fmt = a->channel_layouts[i], bfmt;
 219             if (!fmt || !KNOWN(fmt))
 220                 continue;
 221             bfmt = FF_COUNT2LAYOUT(av_get_channel_layout_nb_channels(fmt));
 222             for (j = 0; j < b->nb_channel_layouts; j++)
 223                 if (b->channel_layouts[j] == bfmt)
 224                     ret->channel_layouts[ret_nb++] = a->channel_layouts[i];
 225         }
 226         /* 1st round: swap to prepare 2nd round; 2nd round: put it back */
 227         FFSWAP(AVFilterChannelLayouts *, a, b);
 228     }
 229     /* a[generic] intersect b[generic] */
 230     for (i = 0; i < a->nb_channel_layouts; i++) {
 231         if (KNOWN(a->channel_layouts[i]))
 232             continue;
 233         for (j = 0; j < b->nb_channel_layouts; j++)
 234             if (a->channel_layouts[i] == b->channel_layouts[j])
 235                 ret->channel_layouts[ret_nb++] = a->channel_layouts[i];
 236     }
 237
 238     ret->nb_channel_layouts = ret_nb;
 239     if (!ret->nb_channel_layouts)
 240         goto fail;
 241     MERGE_REF(ret, a, channel_layouts, AVFilterChannelLayouts, fail);
 242     MERGE_REF(ret, b, channel_layouts, AVFilterChannelLayouts, fail);
 243     return ret;
 244
 245 fail:
 246     if (ret) {
 247         av_freep(&ret->refs);
 248         av_freep(&ret->channel_layouts);
 249     }
 250     av_freep(&ret);
 251     return NULL;
 252 }
 253
 254 int ff_fmt_is_in(int fmt, const int *fmts)
 255 {
 256     const int *p;
 257
 258     for (p = fmts; *p != -1; p++) {
 259         if (fmt == *p)
 260             return 1;
 261     }
 262     return 0;
 263 }
 264
 265 #define COPY_INT_LIST(list_copy, list, type) {                          \
 266     int count = 0;                                                      \
 267     if (list)                                                           \
 268         for (count = 0; list[count] != -1; count++)                     \
 269             ;                                                           \
 270     list_copy = av_calloc(count+1, sizeof(type));                       \
 271     if (list_copy) {                                                    \
 272         memcpy(list_copy, list, sizeof(type) * count);                  \
 273         list_copy[count] = -1;                                          \
 274     }                                                                   \
 275 }
 276
 277 #define MAKE_FORMAT_LIST(type, field, count_field)                      \
 278     type *formats;                                                      \
 279     int count = 0;                                                      \
 280     if (fmts)                                                           \
 281         for (count = 0; fmts[count] != -1; count++)                     \
 282             ;                                                           \
 283     formats = av_mallocz(sizeof(*formats));                             \
 284     if (!formats) return NULL;                                          \
 285     formats->count_field = count;                                       \
 286     if (count) {                                                        \
 287         formats->field = av_malloc_array(count, sizeof(*formats->field));      \
 288         if (!formats->field) {                                          \
 289             av_free(formats);                                           \
 290             return NULL;                                                \
 291         }                                                               \
 292     }
 293
 294 AVFilterFormats *ff_make_format_list(const int *fmts)
 295 {
 296     MAKE_FORMAT_LIST(AVFilterFormats, formats, nb_formats);
 297     while (count--)
 298         formats->formats[count] = fmts[count];
 299
 300     return formats;
 301 }
 302
 303 AVFilterChannelLayouts *avfilter_make_format64_list(const int64_t *fmts)
 304 {
 305     MAKE_FORMAT_LIST(AVFilterChannelLayouts,
 306                      channel_layouts, nb_channel_layouts);
 307     if (count)
 308         memcpy(formats->channel_layouts, fmts,
 309                sizeof(*formats->channel_layouts) * count);
 310
 311     return formats;
 312 }
 313
 314 #define ADD_FORMAT(f, fmt, type, list, nb)                  \
 315 do {                                                        \
 316     type *fmts;                                             \
 317                                                             \
 318     if (!(*f) && !(*f = av_mallocz(sizeof(**f))))           \
 319         return AVERROR(ENOMEM);                             \
 320                                                             \
 321     fmts = av_realloc((*f)->list,                           \
 322                       sizeof(*(*f)->list) * ((*f)->nb + 1));\
 323     if (!fmts) {                                            \
 324         av_freep(&f);                                       \
 325         return AVERROR(ENOMEM);                             \
 326     }                                                       \
 327                                                             \
 328     (*f)->list = fmts;                                      \
 329     (*f)->list[(*f)->nb++] = fmt;                           \
 330 } while (0)
 331
 332 int ff_add_format(AVFilterFormats **avff, int64_t fmt)
 333 {
 334     ADD_FORMAT(avff, fmt, int, formats, nb_formats);
 335     return 0;
 336 }
 337
 338 int ff_add_channel_layout(AVFilterChannelLayouts **l, uint64_t channel_layout)
 339 {
 340     av_assert1(!(*l && (*l)->all_layouts));
 341     ADD_FORMAT(l, channel_layout, uint64_t, channel_layouts, nb_channel_layouts);
 342     return 0;
 343 }
 344
 345 AVFilterFormats *ff_all_formats(enum AVMediaType type)
 346 {
 347     AVFilterFormats *ret = NULL;
 348
 349     if (type == AVMEDIA_TYPE_VIDEO) {
 350         const AVPixFmtDescriptor *desc = NULL;
 351         while ((desc = av_pix_fmt_desc_next(desc))) {
 352             if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
 353                 ff_add_format(&ret, av_pix_fmt_desc_get_id(desc));
 354         }
 355     } else if (type == AVMEDIA_TYPE_AUDIO) {
 356         enum AVSampleFormat fmt = 0;
 357         while (av_get_sample_fmt_name(fmt)) {
 358             ff_add_format(&ret, fmt);
 359             fmt++;
 360         }
 361     }
 362
 363     return ret;
 364 }
 365
 366 const int64_t avfilter_all_channel_layouts[] = {
 367 #include "all_channel_layouts.inc"
 368     -1
 369 };
 370
 371 // AVFilterFormats *avfilter_make_all_channel_layouts(void)
 372 // {
 373 //     return avfilter_make_format64_list(avfilter_all_channel_layouts);
 374 // }
 375
 376 AVFilterFormats *ff_planar_sample_fmts(void)
 377 {
 378     AVFilterFormats *ret = NULL;
 379     int fmt;
 380
 381     for (fmt = 0; av_get_bytes_per_sample(fmt)>0; fmt++)
 382         if (av_sample_fmt_is_planar(fmt))
 383             ff_add_format(&ret, fmt);
 384
 385     return ret;
 386 }
 387
 388 AVFilterFormats *ff_all_samplerates(void)
 389 {
 390     AVFilterFormats *ret = av_mallocz(sizeof(*ret));
 391     return ret;
 392 }
 393
 394 AVFilterChannelLayouts *ff_all_channel_layouts(void)
 395 {
 396     AVFilterChannelLayouts *ret = av_mallocz(sizeof(*ret));
 397     if (!ret)
 398         return NULL;
 399     ret->all_layouts = 1;
 400     return ret;
 401 }
 402
 403 AVFilterChannelLayouts *ff_all_channel_counts(void)
 404 {
 405     AVFilterChannelLayouts *ret = av_mallocz(sizeof(*ret));
 406     if (!ret)
 407         return NULL;
 408     ret->all_layouts = ret->all_counts = 1;
 409     return ret;
 410 }
 411
 412 #define FORMATS_REF(f, ref)                                          \
 413 do {                                                                 \
 414     *ref = f;                                                        \
 415     f->refs = av_realloc(f->refs, sizeof(*f->refs) * ++f->refcount); \
 416     f->refs[f->refcount-1] = ref;                                    \
 417 } while (0)
 418
 419 void ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
 420 {
 421     FORMATS_REF(f, ref);
 422 }
 423
 424 void ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
 425 {
 426     FORMATS_REF(f, ref);
 427 }
 428
 429 #define FIND_REF_INDEX(ref, idx)            \
 430 do {                                        \
 431     int i;                                  \
 432     for (i = 0; i < (*ref)->refcount; i ++) \
 433         if((*ref)->refs[i] == ref) {        \
 434             idx = i;                        \
 435             break;                          \
 436         }                                   \
 437 } while (0)
 438
 439 #define FORMATS_UNREF(ref, list)                                   \
 440 do {                                                               \
 441     int idx = -1;                                                  \
 442                                                                    \
 443     if (!*ref)                                                     \
 444         return;                                                    \
 445                                                                    \
 446     FIND_REF_INDEX(ref, idx);                                      \
 447                                                                    \
 448     if (idx >= 0)                                                  \
 449         memmove((*ref)->refs + idx, (*ref)->refs + idx + 1,        \
 450             sizeof(*(*ref)->refs) * ((*ref)->refcount - idx - 1)); \
 451                                                                    \
 452     if(!--(*ref)->refcount) {                                      \
 453         av_free((*ref)->list);                                     \
 454         av_free((*ref)->refs);                                     \
 455         av_free(*ref);                                             \
 456     }                                                              \
 457     *ref = NULL;                                                   \
 458 } while (0)
 459
 460 void ff_formats_unref(AVFilterFormats **ref)
 461 {
 462     FORMATS_UNREF(ref, formats);
 463 }
 464
 465 void ff_channel_layouts_unref(AVFilterChannelLayouts **ref)
 466 {
 467     FORMATS_UNREF(ref, channel_layouts);
 468 }
 469
 470 #define FORMATS_CHANGEREF(oldref, newref)       \
 471 do {                                            \
 472     int idx = -1;                               \
 473                                                 \
 474     FIND_REF_INDEX(oldref, idx);                \
 475                                                 \
 476     if (idx >= 0) {                             \
 477         (*oldref)->refs[idx] = newref;          \
 478         *newref = *oldref;                      \
 479         *oldref = NULL;                         \
 480     }                                           \
 481 } while (0)
 482
 483 void ff_channel_layouts_changeref(AVFilterChannelLayouts **oldref,
 484                                   AVFilterChannelLayouts **newref)
 485 {
 486     FORMATS_CHANGEREF(oldref, newref);
 487 }
 488
 489 void ff_formats_changeref(AVFilterFormats **oldref, AVFilterFormats **newref)
 490 {
 491     FORMATS_CHANGEREF(oldref, newref);
 492 }
 493
 494 #define SET_COMMON_FORMATS(ctx, fmts, in_fmts, out_fmts, ref, list) \
 495 {                                                                   \
 496     int count = 0, i;                                               \
 497                                                                     \
 498     for (i = 0; i < ctx->nb_inputs; i++) {                          \
 499         if (ctx->inputs[i] && !ctx->inputs[i]->out_fmts) {          \
 500             ref(fmts, &ctx->inputs[i]->out_fmts);                   \
 501             count++;                                                \
 502         }                                                           \
 503     }                                                               \
 504     for (i = 0; i < ctx->nb_outputs; i++) {                         \
 505         if (ctx->outputs[i] && !ctx->outputs[i]->in_fmts) {         \
 506             ref(fmts, &ctx->outputs[i]->in_fmts);                   \
 507             count++;                                                \
 508         }                                                           \
 509     }                                                               \
 510                                                                     \
 511     if (!count) {                                                   \
 512         av_freep(&fmts->list);                                      \
 513         av_freep(&fmts->refs);                                      \
 514         av_freep(&fmts);                                            \
 515     }                                                               \
 516 }
 517
 518 void ff_set_common_channel_layouts(AVFilterContext *ctx,
 519                                    AVFilterChannelLayouts *layouts)
 520 {
 521     SET_COMMON_FORMATS(ctx, layouts, in_channel_layouts, out_channel_layouts,
 522                        ff_channel_layouts_ref, channel_layouts);
 523 }
 524
 525 void ff_set_common_samplerates(AVFilterContext *ctx,
 526                                AVFilterFormats *samplerates)
 527 {
 528     SET_COMMON_FORMATS(ctx, samplerates, in_samplerates, out_samplerates,
 529                        ff_formats_ref, formats);
 530 }
 531
 532 /**
 533  * A helper for query_formats() which sets all links to the same list of
 534  * formats. If there are no links hooked to this filter, the list of formats is
 535  * freed.
 536  */
 537 void ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
 538 {
 539     SET_COMMON_FORMATS(ctx, formats, in_formats, out_formats,
 540                        ff_formats_ref, formats);
 541 }
 542
 543 static int default_query_formats_common(AVFilterContext *ctx,
 544                                         AVFilterChannelLayouts *(layouts)(void))
 545 {
 546     enum AVMediaType type = ctx->inputs  && ctx->inputs [0] ? ctx->inputs [0]->type :
 547                             ctx->outputs && ctx->outputs[0] ? ctx->outputs[0]->type :
 548                             AVMEDIA_TYPE_VIDEO;
 549
 550     ff_set_common_formats(ctx, ff_all_formats(type));
 551     if (type == AVMEDIA_TYPE_AUDIO) {
 552         ff_set_common_channel_layouts(ctx, layouts());
 553         ff_set_common_samplerates(ctx, ff_all_samplerates());
 554     }
 555
 556     return 0;
 557 }
 558
 559 int ff_default_query_formats(AVFilterContext *ctx)
 560 {
 561     return default_query_formats_common(ctx, ff_all_channel_layouts);
 562 }
 563
 564 int ff_query_formats_all(AVFilterContext *ctx)
 565 {
 566     return default_query_formats_common(ctx, ff_all_channel_counts);
 567 }
 568
 569 /* internal functions for parsing audio format arguments */
 570
 571 int ff_parse_pixel_format(enum AVPixelFormat *ret, const char *arg, void *log_ctx)
 572 {
 573     char *tail;
 574     int pix_fmt = av_get_pix_fmt(arg);
 575     if (pix_fmt == AV_PIX_FMT_NONE) {
 576         pix_fmt = strtol(arg, &tail, 0);
 577         if (*tail || !av_pix_fmt_desc_get(pix_fmt)) {
 578             av_log(log_ctx, AV_LOG_ERROR, "Invalid pixel format '%s'\n", arg);
 579             return AVERROR(EINVAL);
 580         }
 581     }
 582     *ret = pix_fmt;
 583     return 0;
 584 }
 585
 586 int ff_parse_sample_format(int *ret, const char *arg, void *log_ctx)
 587 {
 588     char *tail;
 589     int sfmt = av_get_sample_fmt(arg);
 590     if (sfmt == AV_SAMPLE_FMT_NONE) {
 591         sfmt = strtol(arg, &tail, 0);
 592         if (*tail || av_get_bytes_per_sample(sfmt)<=0) {
 593             av_log(log_ctx, AV_LOG_ERROR, "Invalid sample format '%s'\n", arg);
 594             return AVERROR(EINVAL);
 595         }
 596     }
 597     *ret = sfmt;
 598     return 0;
 599 }
 600
 601 int ff_parse_time_base(AVRational *ret, const char *arg, void *log_ctx)
 602 {
 603     AVRational r;
 604     if(av_parse_ratio(&r, arg, INT_MAX, 0, log_ctx) < 0 ||r.num<=0  ||r.den<=0) {
 605         av_log(log_ctx, AV_LOG_ERROR, "Invalid time base '%s'\n", arg);
 606         return AVERROR(EINVAL);
 607     }
 608     *ret = r;
 609     return 0;
 610 }
 611
 612 int ff_parse_sample_rate(int *ret, const char *arg, void *log_ctx)
 613 {
 614     char *tail;
 615     double srate = av_strtod(arg, &tail);
 616     if (*tail || srate < 1 || (int)srate != srate || srate > INT_MAX) {
 617         av_log(log_ctx, AV_LOG_ERROR, "Invalid sample rate '%s'\n", arg);
 618         return AVERROR(EINVAL);
 619     }
 620     *ret = srate;
 621     return 0;
 622 }
 623
 624 int ff_parse_channel_layout(int64_t *ret, int *nret, const char *arg,
 625                             void *log_ctx)
 626 {
 627     char *tail;
 628     int64_t chlayout, count;
 629
 630     if (nret) {
 631         count = strtol(arg, &tail, 10);
 632         if (*tail == 'c' && !tail[1] && count > 0 && count < 63) {
 633             *nret = count;
 634             *ret = 0;
 635             return 0;
 636         }
 637     }
 638     chlayout = av_get_channel_layout(arg);
 639     if (chlayout == 0) {
 640         chlayout = strtol(arg, &tail, 10);
 641         if (*tail || chlayout == 0) {
 642             av_log(log_ctx, AV_LOG_ERROR, "Invalid channel layout '%s'\n", arg);
 643             return AVERROR(EINVAL);
 644         }
 645     }
 646     *ret = chlayout;
 647     if (nret)
 648         *nret = av_get_channel_layout_nb_channels(chlayout);
 649     return 0;
 650 }
 651
 652 #ifdef TEST
 653
 654 #undef printf
 655
 656 int main(void)
 657 {
 658     const int64_t *cl;
 659     char buf[512];
 660
 661     for (cl = avfilter_all_channel_layouts; *cl != -1; cl++) {
 662         av_get_channel_layout_string(buf, sizeof(buf), -1, *cl);
 663         printf("%s\n", buf);
 664     }
 665
 666     return 0;
 667 }
 668
 669 #endif
 670