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 "avfilter.h"
  23
  24 /**
  25  * Add all refs from a to ret and destroy a.
  26  */
  27 static void merge_ref(AVFilterFormats *ret, AVFilterFormats *a)
  28 {
  29     int i;
  30
  31     for(i = 0; i < a->refcount; i ++) {
  32         ret->refs[ret->refcount] = a->refs[i];
  33         *ret->refs[ret->refcount++] = ret;
  34     }
  35
  36     av_free(a->refs);
  37     av_free(a->formats);
  38     av_free(a);
  39 }
  40
  41 AVFilterFormats *avfilter_merge_formats(AVFilterFormats *a, AVFilterFormats *b)
  42 {
  43     AVFilterFormats *ret;
  44     unsigned i, j, k = 0;
  45
  46     ret = av_mallocz(sizeof(AVFilterFormats));
  47
  48     /* merge list of formats */
  49     ret->formats = av_malloc(sizeof(*ret->formats) * FFMIN(a->format_count,
  50                                                            b->format_count));
  51     for(i = 0; i < a->format_count; i ++)
  52         for(j = 0; j < b->format_count; j ++)
  53             if(a->formats[i] == b->formats[j])
  54                 ret->formats[k++] = a->formats[i];
  55
  56     ret->format_count = k;
  57     /* check that there was at least one common format */
  58     if(!ret->format_count) {
  59         av_free(ret->formats);
  60         av_free(ret);
  61         return NULL;
  62     }
  63
  64     ret->refs = av_malloc(sizeof(AVFilterFormats**)*(a->refcount+b->refcount));
  65
  66     merge_ref(ret, a);
  67     merge_ref(ret, b);
  68
  69     return ret;
  70 }
  71
  72 AVFilterFormats *avfilter_make_format_list(int len, ...)
  73 {
  74     AVFilterFormats *ret;
  75     int i;
  76     va_list vl;
  77
  78     ret = av_mallocz(sizeof(AVFilterFormats));
  79     ret->formats = av_malloc(sizeof(*ret->formats) * len);
  80     ret->format_count = len;
  81
  82     va_start(vl, len);
  83     for(i = 0; i < len; i ++)
  84         ret->formats[i] = va_arg(vl, int);
  85     va_end(vl);
  86
  87     return ret;
  88 }
  89
  90 AVFilterFormats *avfilter_all_colorspaces(void)
  91 {
  92     AVFilterFormats *ret;
  93     int i;
  94
  95     ret = av_mallocz(sizeof(AVFilterFormats));
  96     ret->formats = av_malloc(sizeof(*ret->formats) * PIX_FMT_NB);
  97     ret->format_count = PIX_FMT_NB;
  98
  99     for(i = 0; i < PIX_FMT_NB; i ++)
 100         ret->formats[i] = i;
 101
 102     return ret;
 103 }
 104
 105 void avfilter_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
 106 {
 107     *ref = f;
 108     f->refs = av_realloc(f->refs, sizeof(AVFilterFormats**) * ++f->refcount);
 109     f->refs[f->refcount-1] = ref;
 110 }
 111
 112 static int find_ref_index(AVFilterFormats **ref)
 113 {
 114     int i;
 115     for(i = 0; i < (*ref)->refcount; i ++)
 116         if((*ref)->refs[i] == ref)
 117             return i;
 118     return -1;
 119 }
 120
 121 void avfilter_formats_unref(AVFilterFormats **ref)
 122 {
 123     int idx = find_ref_index(ref);
 124
 125     if(idx >= 0)
 126         memmove((*ref)->refs + idx, (*ref)->refs + idx+1,
 127             sizeof(AVFilterFormats**) * ((*ref)->refcount-idx-1));
 128
 129     if(!--(*ref)->refcount) {
 130         av_free((*ref)->formats);
 131         av_free((*ref)->refs);
 132         av_free(*ref);
 133     }
 134     *ref = NULL;
 135 }
 136
 137 void avfilter_formats_changeref(AVFilterFormats **oldref,
 138                                 AVFilterFormats **newref)
 139 {
 140     int idx = find_ref_index(oldref);
 141
 142     if(idx >= 0) {
 143         (*oldref)->refs[idx] = newref;
 144         *newref = *oldref;
 145         *oldref = NULL;
 146     }
 147 }
 148