1. ffmpeg
  2. Commit 7f1af825f8bbb2fd911284a68f1c98e784e0fda4
Browse code

Add fifo filter.

Originally committed as revision 24896 to svn://svn.ffmpeg.org/ffmpeg/trunk

Stefano Sabatini authored on 2010/08/24 17:38:00
Showing 5 changed files
doc/filters.texi
History View file @ 7f1af82
... ... 
@@ -55,6 +55,15 @@ corner of the input image.
55 55
56 56 
 The default value of @var{width} and @var{height} is 0.
57 57
58 
+@section fifo
59 
+
60 
+Buffer input images and send them when they are requested.
61 
+
62 
+This filter is mainly useful when auto-inserted by the libavfilter
63 
+framework.
64 
+
65 
+The filter does not take parameters.
66 
+
58 67 
 @section format
59 68
60 69 
 Convert the input video to one of the specified pixel formats.
libavfilter/Makefile
History View file @ 7f1af82
... ... 
@@ -18,6 +18,7 @@ OBJS-$(CONFIG_ANULL_FILTER)                  += af_anull.o
18 18
19 19 
 OBJS-$(CONFIG_ASPECT_FILTER)                 += vf_aspect.o
20 20 
 OBJS-$(CONFIG_CROP_FILTER)                   += vf_crop.o
21 
+OBJS-$(CONFIG_FIFO_FILTER)                   += vf_fifo.o
21 22 
 OBJS-$(CONFIG_FORMAT_FILTER)                 += vf_format.o
22 23 
 OBJS-$(CONFIG_HFLIP_FILTER)                  += vf_hflip.o
23 24 
 OBJS-$(CONFIG_NOFORMAT_FILTER)               += vf_format.o
libavfilter/allfilters.c
History View file @ 7f1af82
... ... 
@@ -38,6 +38,7 @@ void avfilter_register_all(void)
38 38
39 39 
     REGISTER_FILTER (ASPECT,      aspect,      vf);
40 40 
     REGISTER_FILTER (CROP,        crop,        vf);
41 
+    REGISTER_FILTER (FIFO,        fifo,        vf);
41 42 
     REGISTER_FILTER (FORMAT,      format,      vf);
42 43 
     REGISTER_FILTER (HFLIP,       hflip,       vf);
43 44 
     REGISTER_FILTER (NOFORMAT,    noformat,    vf);
libavfilter/avfilter.h
History View file @ 7f1af82
... ... 
@@ -25,7 +25,7 @@
25 25 
 #include "libavutil/avutil.h"
26 26
27 27 
 #define LIBAVFILTER_VERSION_MAJOR  1
28 
-#define LIBAVFILTER_VERSION_MINOR 37
28 
+#define LIBAVFILTER_VERSION_MINOR 38
29 29 
 #define LIBAVFILTER_VERSION_MICRO  0
30 30
31 31 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
libavfilter/vf_fifo.c
History View file @ 7f1af82
32 32 
new file mode 100644
... ... 
@@ -0,0 +1,119 @@
0 
+/*
1 
+ * copyright (c) 2007 Bobby Bingham
2 
+ *
3 
+ * This file is part of FFmpeg.
4 
+ *
5 
+ * FFmpeg is free software; you can redistribute it and/or
6 
+ * modify it under the terms of the GNU Lesser General Public
7 
+ * License as published by the Free Software Foundation; either
8 
+ * version 2.1 of the License, or (at your option) any later version.
9 
+ *
10 
+ * FFmpeg is distributed in the hope that it will be useful,
11 
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 
+ * Lesser General Public License for more details.
14 
+ *
15 
+ * You should have received a copy of the GNU Lesser General Public
16 
+ * License along with FFmpeg; if not, write to the Free Software
17 
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 
+ */
19 
+
20 
+/**
21 
+ * @file
22 
+ * FIFO buffering video filter
23 
+ */
24 
+
25 
+#include "avfilter.h"
26 
+
27 
+typedef struct BufPic {
28 
+    AVFilterBufferRef *picref;
29 
+    struct BufPic     *next;
30 
+} BufPic;
31 
+
32 
+typedef struct {
33 
+    BufPic  root;
34 
+    BufPic *last;   ///< last buffered picture
35 
+} FifoContext;
36 
+
37 
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
38 
+{
39 
+    FifoContext *fifo = ctx->priv;
40 
+    fifo->last = &fifo->root;
41 
+
42 
+    av_log(ctx, AV_LOG_INFO, "\n");
43 
+    return 0;
44 
+}
45 
+
46 
+static av_cold void uninit(AVFilterContext *ctx)
47 
+{
48 
+    FifoContext *fifo = ctx->priv;
49 
+    BufPic *pic, *tmp;
50 
+
51 
+    for (pic = fifo->root.next; pic; pic = tmp) {
52 
+        tmp = pic->next;
53 
+        avfilter_unref_buffer(pic->picref);
54 
+        av_free(pic);
55 
+    }
56 
+}
57 
+
58 
+static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
59 
+{
60 
+    FifoContext *fifo = inlink->dst->priv;
61 
+
62 
+    fifo->last->next = av_mallocz(sizeof(BufPic));
63 
+    fifo->last = fifo->last->next;
64 
+    fifo->last->picref = picref;
65 
+}
66 
+
67 
+static void end_frame(AVFilterLink *inlink) { }
68 
+
69 
+static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir) { }
70 
+
71 
+static int request_frame(AVFilterLink *outlink)
72 
+{
73 
+    FifoContext *fifo = outlink->src->priv;
74 
+    BufPic *tmp;
75 
+    int ret;
76 
+
77 
+    if (!fifo->root.next) {
78 
+        if ((ret = avfilter_request_frame(outlink->src->inputs[0]) < 0))
79 
+            return ret;
80 
+    }
81 
+
82 
+    /* by doing this, we give ownership of the reference to the next filter,
83 
+     * so we don't have to worry about dereferencing it ourselves. */
84 
+    avfilter_start_frame(outlink, fifo->root.next->picref);
85 
+    avfilter_draw_slice (outlink, 0, outlink->h, 1);
86 
+    avfilter_end_frame  (outlink);
87 
+
88 
+    if (fifo->last == fifo->root.next)
89 
+        fifo->last = &fifo->root;
90 
+    tmp = fifo->root.next->next;
91 
+    av_free(fifo->root.next);
92 
+    fifo->root.next = tmp;
93 
+
94 
+    return 0;
95 
+}
96 
+
97 
+AVFilter avfilter_vf_fifo = {
98 
+    .name      = "fifo",
99 
+    .description = NULL_IF_CONFIG_SMALL("Buffer input images and send them when they are requested."),
100 
+
101 
+    .init      = init,
102 
+    .uninit    = uninit,
103 
+
104 
+    .priv_size = sizeof(FifoContext),
105 
+
106 
+    .inputs    = (AVFilterPad[]) {{ .name            = "default",
107 
+                                    .type            = AVMEDIA_TYPE_VIDEO,
108 
+                                    .get_video_buffer= avfilter_null_get_video_buffer,
109 
+                                    .start_frame     = start_frame,
110 
+                                    .draw_slice      = draw_slice,
111 
+                                    .end_frame       = end_frame,
112 
+                                    .rej_perms       = AV_PERM_REUSE2, },
113 
+                                  { .name = NULL}},
114 
+    .outputs   = (AVFilterPad[]) {{ .name            = "default",
115 
+                                    .type            = AVMEDIA_TYPE_VIDEO,
116 
+                                    .request_frame   = request_frame, },
117 
+                                  { .name = NULL}},
118 
+};