1. ffmpeg
  2. Commit 3922deb5773396f14df9c7ff9e60f84bf185b945
Browse code

Add video filter to manipulate aspect ratio

Originally committed as revision 22573 to svn://svn.ffmpeg.org/ffmpeg/trunk

Bobby Bingham authored on 2010/03/17 12:43:14
Showing 3 changed files
libavfilter/Makefile
History View file @ 3922deb
... ... 
@@ -14,10 +14,12 @@ OBJS = allfilters.o                                                     \
14 14 
        graphparser.o                                                    \
15 15 
        parseutils.o                                                     \
16 16
17 
+OBJS-$(CONFIG_ASPECT_FILTER)                 += vf_aspect.o
17 18 
 OBJS-$(CONFIG_CROP_FILTER)                   += vf_crop.o
18 19 
 OBJS-$(CONFIG_FORMAT_FILTER)                 += vf_format.o
19 20 
 OBJS-$(CONFIG_NOFORMAT_FILTER)               += vf_format.o
20 21 
 OBJS-$(CONFIG_NULL_FILTER)                   += vf_null.o
22 
+OBJS-$(CONFIG_PIXELASPECT_FILTER)            += vf_aspect.o
21 23 
 OBJS-$(CONFIG_SCALE_FILTER)                  += vf_scale.o
22 24 
 OBJS-$(CONFIG_SLICIFY_FILTER)                += vf_slicify.o
23 25 
 OBJS-$(CONFIG_VFLIP_FILTER)                  += vf_vflip.o
libavfilter/allfilters.c
History View file @ 3922deb
... ... 
@@ -34,15 +34,17 @@ void avfilter_register_all(void)
34 34 
         return;
35 35 
     initialized = 1;
36 36
37 
+    REGISTER_FILTER (ASPECT, aspect, vf);
37 38 
     REGISTER_FILTER (CROP, crop, vf);
38 39 
     REGISTER_FILTER (FORMAT, format, vf);
39 40 
     REGISTER_FILTER (NOFORMAT, noformat, vf);
40 41 
     REGISTER_FILTER (NULL, null, vf);
42 
+    REGISTER_FILTER (PIXELASPECT, pixelaspect, vf);
41 43 
     REGISTER_FILTER (SCALE, scale, vf);
42 44 
     REGISTER_FILTER (SLICIFY, slicify, vf);
43 45 
     REGISTER_FILTER (VFLIP, vflip, vf);
44 46
45 47 
     REGISTER_FILTER (NULLSRC, nullsrc, vsrc);
46 48
47 
-    REGISTER_FILTER(NULLSINK, nullsink, vsink);
49 
+    REGISTER_FILTER (NULLSINK, nullsink, vsink);
48 50 
 }
libavfilter/vf_aspect.c
History View file @ 3922deb
49 51 
new file mode 100644
... ... 
@@ -0,0 +1,135 @@
0 
+/*
1 
+ * Aspect ratio modification video filter
2 
+ * Copyright (c) 2010 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_aspect.c
23 
+ * aspect ratio modification video filter
24 
+ */
25 
+
26 
+#include "avfilter.h"
27 
+
28 
+typedef struct {
29 
+    AVRational aspect;
30 
+} AspectContext;
31 
+
32 
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
33 
+{
34 
+    AspectContext *aspect = ctx->priv;
35 
+    double  ratio;
36 
+    int64_t gcd;
37 
+
38 
+    if(args) {
39 
+        if(sscanf(args, "%d:%d", &aspect->aspect.num, &aspect->aspect.den) < 2) {
40 
+            if(sscanf(args, "%lf", &ratio) < 1)
41 
+                return -1;
42 
+            aspect->aspect = av_d2q(ratio, 100);
43 
+        } else {
44 
+            gcd = av_gcd(FFABS(aspect->aspect.num), FFABS(aspect->aspect.den));
45 
+            if(gcd) {
46 
+                aspect->aspect.num /= gcd;
47 
+                aspect->aspect.den /= gcd;
48 
+            }
49 
+        }
50 
+    }
51 
+
52 
+    if(aspect->aspect.den == 0)
53 
+        aspect->aspect = (AVRational) {0, 1};
54 
+
55 
+    return 0;
56 
+}
57 
+
58 
+
59 
+static AVFilterPicRef *get_video_buffer(AVFilterLink *link, int perms,
60 
+                                        int w, int h)
61 
+{
62 
+    return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);
63 
+}
64 
+
65 
+static void start_frame(AVFilterLink *link, AVFilterPicRef *picref)
66 
+{
67 
+    AspectContext *aspect = link->dst->priv;
68 
+
69 
+    picref->pixel_aspect = aspect->aspect;
70 
+    avfilter_start_frame(link->dst->outputs[0], picref);
71 
+}
72 
+
73 
+static void end_frame(AVFilterLink *link)
74 
+{
75 
+    avfilter_end_frame(link->dst->outputs[0]);
76 
+}
77 
+
78 
+#if CONFIG_ASPECT_FILTER
79 
+/* for aspect filter, convert from frame aspect ratio to pixel aspect ratio */
80 
+static int frameaspect_config_props(AVFilterLink *inlink)
81 
+{
82 
+    AspectContext *aspect = inlink->dst->priv;
83 
+
84 
+    av_reduce(&aspect->aspect.num, &aspect->aspect.den,
85 
+               aspect->aspect.num * inlink->h,
86 
+               aspect->aspect.den * inlink->w, 100);
87 
+
88 
+    return 0;
89 
+}
90 
+
91 
+AVFilter avfilter_vf_aspect = {
92 
+    .name      = "aspect",
93 
+    .description = NULL_IF_CONFIG_SMALL("Set the frame aspect ratio."),
94 
+
95 
+    .init      = init,
96 
+
97 
+    .priv_size = sizeof(AspectContext),
98 
+
99 
+    .inputs    = (AVFilterPad[]) {{ .name             = "default",
100 
+                                    .type             = CODEC_TYPE_VIDEO,
101 
+                                    .config_props     = frameaspect_config_props,
102 
+                                    .get_video_buffer = get_video_buffer,
103 
+                                    .start_frame      = start_frame,
104 
+                                    .end_frame        = end_frame },
105 
+                                  { .name = NULL}},
106 
+
107 
+    .outputs   = (AVFilterPad[]) {{ .name             = "default",
108 
+                                    .type             = CODEC_TYPE_VIDEO, },
109 
+                                  { .name = NULL}},
110 
+};
111 
+#endif /* CONFIG_ASPECT_FILTER */
112 
+
113 
+#if CONFIG_PIXELASPECT_FILTER
114 
+AVFilter avfilter_vf_pixelaspect = {
115 
+    .name      = "pixelaspect",
116 
+    .description = NULL_IF_CONFIG_SMALL("Set the pixel aspect ratio."),
117 
+
118 
+    .init      = init,
119 
+
120 
+    .priv_size = sizeof(AspectContext),
121 
+
122 
+    .inputs    = (AVFilterPad[]) {{ .name             = "default",
123 
+                                    .type             = CODEC_TYPE_VIDEO,
124 
+                                    .get_video_buffer = get_video_buffer,
125 
+                                    .start_frame      = start_frame,
126 
+                                    .end_frame        = end_frame },
127 
+                                  { .name = NULL}},
128 
+
129 
+    .outputs   = (AVFilterPad[]) {{ .name             = "default",
130 
+                                    .type             = CODEC_TYPE_VIDEO, },
131 
+                                  { .name = NULL}},
132 
+};
133 
+#endif /* CONFIG_PIXELASPECT_FILTER */
134 
+