FFmpeg
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 
45 {
46  FlipContext *flip = link->dst->priv;
48 
49  flip->vsub = desc->log2_chroma_h;
50 
51  return 0;
52 }
53 
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:2522
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
Main libavfilter public API header.
const char * desc
Definition: nvenc.c:68
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
Definition: video.c:99
#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:60
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
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
#define height
static const AVOption vflip_options[]
Definition: vf_vflip.c:38
A filter pad used for either input or output.
Definition: internal.h:54
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
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:136
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
AVFILTER_DEFINE_CLASS(vflip)
common internal API header
uint8_t w
Definition: llviddspenc.c:38
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
static int config_input(AVFilterLink *link)
Definition: vf_vflip.c:44
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
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
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a link
AVFilter ff_vf_vflip
Definition: vf_vflip.c:113
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
#define flags(name, subs,...)
Definition: cbs_av1.c:561
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
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