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vf_vflip.c
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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
23  * video vertical flip filter
24  */
25 
26 #include "libavutil/internal.h"
27 #include "libavutil/opt.h"
28 #include "libavutil/pixdesc.h"
29 #include "avfilter.h"
30 #include "internal.h"
31 #include "video.h"
32 
33 typedef struct FlipContext {
34  const AVClass *class;
35  int vsub; ///< vertical chroma subsampling
36 } FlipContext;
37 
38 static const AVOption vflip_options[] = {
39  { NULL }
40 };
41 
43 
44 static int config_input(AVFilterLink *link)
45 {
46  FlipContext *flip = link->dst->priv;
48 
49  flip->vsub = desc->log2_chroma_h;
50 
51  return 0;
52 }
53 
54 static AVFrame *get_video_buffer(AVFilterLink *link, int w, int h)
55 {
56  FlipContext *flip = link->dst->priv;
57  AVFrame *frame;
58  int i;
59 
60  frame = ff_get_video_buffer(link->dst->outputs[0], w, h);
61  if (!frame)
62  return NULL;
63 
64  for (i = 0; i < 4; i ++) {
65  int vsub = i == 1 || i == 2 ? flip->vsub : 0;
66  int height = AV_CEIL_RSHIFT(h, vsub);
67 
68  if (frame->data[i]) {
69  frame->data[i] += (height - 1) * frame->linesize[i];
70  frame->linesize[i] = -frame->linesize[i];
71  }
72  }
73 
74  return frame;
75 }
76 
78 {
79  FlipContext *flip = link->dst->priv;
80  int i;
81 
82  for (i = 0; i < 4; i ++) {
83  int vsub = i == 1 || i == 2 ? flip->vsub : 0;
84  int height = AV_CEIL_RSHIFT(link->h, vsub);
85 
86  if (frame->data[i]) {
87  frame->data[i] += (height - 1) * frame->linesize[i];
88  frame->linesize[i] = -frame->linesize[i];
89  }
90  }
91 
92  return ff_filter_frame(link->dst->outputs[0], frame);
93 }
95  {
96  .name = "default",
97  .type = AVMEDIA_TYPE_VIDEO,
98  .get_video_buffer = get_video_buffer,
99  .filter_frame = filter_frame,
100  .config_props = config_input,
101  },
102  { NULL }
103 };
104 
106  {
107  .name = "default",
108  .type = AVMEDIA_TYPE_VIDEO,
109  },
110  { NULL }
111 };
112 
114  .name = "vflip",
115  .description = NULL_IF_CONFIG_SMALL("Flip the input video vertically."),
116  .priv_size = sizeof(FlipContext),
117  .priv_class = &vflip_class,
118  .inputs = avfilter_vf_vflip_inputs,
119  .outputs = avfilter_vf_vflip_outputs,
121 };
#define NULL
Definition: coverity.c:32
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2263
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
AVOption.
Definition: opt.h:245
Main libavfilter public API header.
const char * desc
Definition: nvenc.c:99
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
Definition: video.c:76
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:125
const char * name
Pad name.
Definition: internal.h:59
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1189
AVOptions.
static const AVFilterPad avfilter_vf_vflip_inputs[]
Definition: vf_vflip.c:94
static int filter_frame(AVFilterLink *link, AVFrame *frame)
Definition: vf_vflip.c:77
static AVFrame * frame
#define height
static const AVOption vflip_options[]
Definition: vf_vflip.c:38
A filter pad used for either input or output.
Definition: internal.h:53
uint8_t log2_chroma_h
Amount to shift the luma height right to find the chroma height.
Definition: pixdesc.h:101
static void flip(AVCodecContext *avctx, AVFrame *frame)
Definition: rawdec.c:134
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
void * priv
private data for use by the filter
Definition: avfilter.h:322
AVFILTER_DEFINE_CLASS(vflip)
common internal API header
static const AVFilterPad outputs[]
Definition: af_afftfilt.c:386
static int config_input(AVFilterLink *link)
Definition: vf_vflip.c:44
static const AVFilterPad inputs[]
Definition: af_afftfilt.c:376
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:215
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
const char * name
Filter name.
Definition: avfilter.h:148
AVFilter ff_vf_vflip
Definition: vf_vflip.c:113
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:319
static int flags
Definition: cpu.c:47
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
static const AVFilterPad avfilter_vf_vflip_outputs[]
Definition: vf_vflip.c:105
static AVFrame * get_video_buffer(AVFilterLink *link, int w, int h)
Definition: vf_vflip.c:54
int vsub
vertical chroma subsampling
Definition: vf_vflip.c:35
internal API functions
#define AV_CEIL_RSHIFT(a, b)
Definition: common.h:58