libavfilter/vf_format.c

   1 /*
   2  * copyright (c) 2007 Bobby Bingham
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 /**
  22  * @file libavfilter/vf_format.c
  23  * video format and noformat filters
  24  */
  25
  26 #include "avfilter.h"
  27
  28 typedef struct {
  29     /**
  30      * List of flags telling if a given image format has been listed
  31      * as argument to the filter.
  32      */
  33     int listed_pix_fmt_flags[PIX_FMT_NB];
  34 } FormatContext;
  35
  36 #define PIX_FMT_NAME_MAXSIZE 32
  37
  38 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
  39 {
  40     FormatContext *format = ctx->priv;
  41     const char *cur, *sep;
  42     char             pix_fmt_name[PIX_FMT_NAME_MAXSIZE];
  43     int              pix_fmt_name_len;
  44     enum PixelFormat pix_fmt;
  45
  46     /* parse the list of formats */
  47     for (cur = args; cur; cur = sep ? sep+1 : NULL) {
  48         if (!(sep = strchr(cur, ':')))
  49             pix_fmt_name_len = strlen(cur);
  50         else
  51             pix_fmt_name_len = sep - cur;
  52         if (pix_fmt_name_len >= PIX_FMT_NAME_MAXSIZE) {
  53             av_log(ctx, AV_LOG_ERROR, "Format name too long\n");
  54             return -1;
  55         }
  56
  57         memcpy(pix_fmt_name, cur, pix_fmt_name_len);
  58         pix_fmt_name[pix_fmt_name_len] = 0;
  59         pix_fmt = avcodec_get_pix_fmt(pix_fmt_name);
  60
  61         if (pix_fmt == PIX_FMT_NONE) {
  62             av_log(ctx, AV_LOG_ERROR, "Unknown pixel format: %s\n", pix_fmt_name);
  63             return -1;
  64         }
  65
  66         format->listed_pix_fmt_flags[pix_fmt] = 1;
  67     }
  68
  69     return 0;
  70 }
  71
  72 static AVFilterFormats *make_format_list(FormatContext *format, int flag)
  73 {
  74     AVFilterFormats *formats;
  75     enum PixelFormat pix_fmt;
  76
  77     formats = av_mallocz(sizeof(AVFilterFormats));
  78     formats->formats = av_malloc(sizeof(enum PixelFormat) * PIX_FMT_NB);
  79
  80     for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++)
  81         if (format->listed_pix_fmt_flags[pix_fmt] == flag)
  82             formats->formats[formats->format_count++] = pix_fmt;
  83
  84     return formats;
  85 }
  86
  87 static int query_formats_format(AVFilterContext *ctx)
  88 {
  89     avfilter_set_common_formats(ctx, make_format_list(ctx->priv, 1));
  90     return 0;
  91 }
  92
  93 static int query_formats_noformat(AVFilterContext *ctx)
  94 {
  95     avfilter_set_common_formats(ctx, make_format_list(ctx->priv, 0));
  96     return 0;
  97 }
  98
  99 static void start_frame(AVFilterLink *link, AVFilterPicRef *picref)
 100 {
 101     avfilter_start_frame(link->dst->outputs[0], picref);
 102 }
 103
 104 static void end_frame(AVFilterLink *link)
 105 {
 106     avfilter_end_frame(link->dst->outputs[0]);
 107 }
 108
 109 static void draw_slice(AVFilterLink *link, int y, int h)
 110 {
 111     avfilter_draw_slice(link->dst->outputs[0], y, h);
 112 }
 113
 114 AVFilter avfilter_vf_format = {
 115     .name      = "format",
 116     .description = "Convert the input video to one of the specified pixel formats.",
 117
 118     .init      = init,
 119
 120     .query_formats = query_formats_format,
 121
 122     .priv_size = sizeof(FormatContext),
 123
 124     .inputs    = (AVFilterPad[]) {{ .name            = "default",
 125                                     .type            = CODEC_TYPE_VIDEO,
 126                                     .start_frame     = start_frame,
 127                                     .draw_slice      = draw_slice,
 128                                     .end_frame       = end_frame, },
 129                                   { .name = NULL}},
 130     .outputs   = (AVFilterPad[]) {{ .name            = "default",
 131                                     .type            = CODEC_TYPE_VIDEO },
 132                                   { .name = NULL}},
 133 };
 134
 135 AVFilter avfilter_vf_noformat = {
 136     .name      = "noformat",
 137     .description = "Force libavfilter not to use any of the specified pixel formats as the input to the next filter.",
 138
 139     .init      = init,
 140
 141     .query_formats = query_formats_noformat,
 142
 143     .priv_size = sizeof(FormatContext),
 144
 145     .inputs    = (AVFilterPad[]) {{ .name            = "default",
 146                                     .type            = CODEC_TYPE_VIDEO,
 147                                     .start_frame     = start_frame,
 148                                     .draw_slice      = draw_slice,
 149                                     .end_frame       = end_frame, },
 150                                   { .name = NULL}},
 151     .outputs   = (AVFilterPad[]) {{ .name            = "default",
 152                                     .type            = CODEC_TYPE_VIDEO },
 153                                   { .name = NULL}},
 154 };