FFmpeg
vf_alphamerge.c
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1 /*
2  * Copyright (c) 2012 Steven Robertson
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  * copy an alpha component from another video's luma
24  */
25 
26 #include <string.h>
27 
28 #include "libavutil/imgutils.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/pixfmt.h"
31 #include "avfilter.h"
32 #include "drawutils.h"
33 #include "formats.h"
34 #include "filters.h"
35 #include "framesync.h"
36 #include "internal.h"
37 #include "video.h"
38 
39 enum { Y, U, V, A };
40 
41 typedef struct AlphaMergeContext {
42  const AVClass *class;
43 
45  uint8_t rgba_map[4];
46 
49 
51 {
52  AVFilterContext *ctx = fs->parent;
53  AlphaMergeContext *s = ctx->priv;
54  AVFrame *main_buf, *alpha_buf;
55  int ret;
56 
57  ret = ff_framesync_dualinput_get_writable(fs, &main_buf, &alpha_buf);
58  if (ret < 0)
59  return ret;
60  if (!alpha_buf)
61  return ff_filter_frame(ctx->outputs[0], main_buf);
62 
63  if (s->is_packed_rgb) {
64  int x, y;
65  uint8_t *pin, *pout;
66  for (y = 0; y < main_buf->height; y++) {
67  pin = alpha_buf->data[0] + y * alpha_buf->linesize[0];
68  pout = main_buf->data[0] + y * main_buf->linesize[0] + s->rgba_map[A];
69  for (x = 0; x < main_buf->width; x++) {
70  *pout = *pin;
71  pin += 1;
72  pout += 4;
73  }
74  }
75  } else {
76  const int main_linesize = main_buf->linesize[A];
77  const int alpha_linesize = alpha_buf->linesize[Y];
78  av_image_copy_plane(main_buf->data[A], main_linesize,
79  alpha_buf->data[Y], alpha_linesize,
80  FFMIN(main_linesize, alpha_linesize), alpha_buf->height);
81  }
82 
83  return ff_filter_frame(ctx->outputs[0], main_buf);
84 }
85 
87 {
88  AlphaMergeContext *s = ctx->priv;
89 
90  s->fs.on_event = do_alphamerge;
91  return 0;
92 }
93 
95 {
96  static const enum AVPixelFormat main_fmts[] = {
101  };
102  static const enum AVPixelFormat alpha_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
103  AVFilterFormats *main_formats = ff_make_format_list(main_fmts);
104  int ret;
105 
106  if ((ret = ff_formats_ref(main_formats, &ctx->inputs[0]->outcfg.formats)) < 0 ||
107  (ret = ff_formats_ref(main_formats, &ctx->outputs[0]->incfg.formats)) < 0)
108  return ret;
109 
110  return ff_formats_ref(ff_make_format_list(alpha_fmts),
111  &ctx->inputs[1]->outcfg.formats);
112 }
113 
115 {
116  AlphaMergeContext *s = inlink->dst->priv;
117  s->is_packed_rgb =
118  ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0 &&
119  inlink->format != AV_PIX_FMT_GBRAP;
120  return 0;
121 }
122 
123 static int config_output(AVFilterLink *outlink)
124 {
125  AVFilterContext *ctx = outlink->src;
126  AlphaMergeContext *s = ctx->priv;
127  AVFilterLink *mainlink = ctx->inputs[0];
128  AVFilterLink *alphalink = ctx->inputs[1];
129  int ret;
130 
131  if (mainlink->w != alphalink->w || mainlink->h != alphalink->h) {
133  "Input frame sizes do not match (%dx%d vs %dx%d).\n",
134  mainlink->w, mainlink->h,
135  alphalink->w, alphalink->h);
136  return AVERROR(EINVAL);
137  }
138 
139  if ((ret = ff_framesync_init_dualinput(&s->fs, ctx)) < 0)
140  return ret;
141 
142  outlink->w = mainlink->w;
143  outlink->h = mainlink->h;
144  outlink->time_base = mainlink->time_base;
145  outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
146  outlink->frame_rate = mainlink->frame_rate;
147 
148  return ff_framesync_configure(&s->fs);
149 }
150 
152 {
153  AlphaMergeContext *s = ctx->priv;
154  return ff_framesync_activate(&s->fs);
155 }
156 
158 {
159  AlphaMergeContext *s = ctx->priv;
160 
161  ff_framesync_uninit(&s->fs);
162 }
163 
164 static const AVFilterPad alphamerge_inputs[] = {
165  {
166  .name = "main",
167  .type = AVMEDIA_TYPE_VIDEO,
168  .config_props = config_input_main,
169  },{
170  .name = "alpha",
171  .type = AVMEDIA_TYPE_VIDEO,
172  },
173 };
174 
175 static const AVFilterPad alphamerge_outputs[] = {
176  {
177  .name = "default",
178  .type = AVMEDIA_TYPE_VIDEO,
179  .config_props = config_output,
180  },
181 };
182 
183 static const AVOption alphamerge_options[] = {
184  { NULL }
185 };
186 
188 
190  .name = "alphamerge",
191  .description = NULL_IF_CONFIG_SMALL("Copy the luma value of the second "
192  "input into the alpha channel of the first input."),
193  .preinit = alphamerge_framesync_preinit,
194  .priv_size = sizeof(AlphaMergeContext),
195  .priv_class = &alphamerge_class,
196  .init = init,
200  .uninit = uninit,
201  .activate = activate,
203 };
ff_framesync_configure
int ff_framesync_configure(FFFrameSync *fs)
Configure a frame sync structure.
Definition: framesync.c:124
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVERROR
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 all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
AlphaMergeContext
Definition: vf_alphamerge.c:41
ff_make_format_list
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:380
ff_framesync_uninit
void ff_framesync_uninit(FFFrameSync *fs)
Free all memory currently allocated.
Definition: framesync.c:290
alphamerge_inputs
static const AVFilterPad alphamerge_inputs[]
Definition: vf_alphamerge.c:164
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1019
V
@ V
Definition: vf_alphamerge.c:39
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AVFrame::width
int width
Definition: frame.h:361
alphamerge_outputs
static const AVFilterPad alphamerge_outputs[]
Definition: vf_alphamerge.c:175
AVOption
AVOption.
Definition: opt.h:247
config_output
static int config_output(AVFilterLink *outlink)
Definition: vf_alphamerge.c:123
AV_PIX_FMT_BGRA
@ AV_PIX_FMT_BGRA
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
AlphaMergeContext::fs
FFFrameSync fs
Definition: vf_alphamerge.c:47
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
FFFrameSync
Frame sync structure.
Definition: framesync.h:146
video.h
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: vf_alphamerge.c:94
config_input_main
static int config_input_main(AVFilterLink *inlink)
Definition: vf_alphamerge.c:114
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:317
av_image_copy_plane
void av_image_copy_plane(uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize, int bytewidth, int height)
Copy image plane from src to dst.
Definition: imgutils.c:374
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
formats.h
AV_PIX_FMT_GBRAP
@ AV_PIX_FMT_GBRAP
planar GBRA 4:4:4:4 32bpp
Definition: pixfmt.h:205
init
static av_cold int init(AVFilterContext *ctx)
Definition: vf_alphamerge.c:86
U
@ U
Definition: vf_alphamerge.c:39
do_alphamerge
static int do_alphamerge(FFFrameSync *fs)
Definition: vf_alphamerge.c:50
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_PIX_FMT_YUVA420P
@ AV_PIX_FMT_YUVA420P
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:101
ff_formats_ref
int ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:553
filters.h
ctx
AVFormatContext * ctx
Definition: movenc.c:48
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:152
AV_PIX_FMT_RGBA
@ AV_PIX_FMT_RGBA
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:93
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
fs
#define fs(width, name, subs,...)
Definition: cbs_vp9.c:259
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_alphamerge.c:157
AlphaMergeContext::rgba_map
uint8_t rgba_map[4]
Definition: vf_alphamerge.c:45
Y
@ Y
Definition: vf_alphamerge.c:39
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:74
AV_PIX_FMT_ABGR
@ AV_PIX_FMT_ABGR
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:94
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
ff_framesync_init_dualinput
int ff_framesync_init_dualinput(FFFrameSync *fs, AVFilterContext *parent)
Initialize a frame sync structure for dualinput.
Definition: framesync.c:358
FRAMESYNC_DEFINE_CLASS
FRAMESYNC_DEFINE_CLASS(alphamerge, AlphaMergeContext, fs)
AV_PIX_FMT_YUVA444P
@ AV_PIX_FMT_YUVA444P
planar YUV 4:4:4 32bpp, (1 Cr & Cb sample per 1x1 Y & A samples)
Definition: pixfmt.h:167
internal.h
AV_PIX_FMT_ARGB
@ AV_PIX_FMT_ARGB
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:92
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
AVFilter
Filter definition.
Definition: avfilter.h:149
ret
ret
Definition: filter_design.txt:187
pixfmt.h
ff_vf_alphamerge
const AVFilter ff_vf_alphamerge
Definition: vf_alphamerge.c:189
AVFrame::height
int height
Definition: frame.h:361
framesync.h
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
avfilter.h
A
@ A
Definition: vf_alphamerge.c:39
alphamerge_options
static const AVOption alphamerge_options[]
Definition: vf_alphamerge.c:183
AVFilterContext
An instance of a filter.
Definition: avfilter.h:346
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:153
ff_fill_rgba_map
int ff_fill_rgba_map(uint8_t *rgba_map, enum AVPixelFormat pix_fmt)
Definition: drawutils.c:33
AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will have its filter_frame() c...
Definition: avfilter.h:138
imgutils.h
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:334
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
ff_framesync_activate
int ff_framesync_activate(FFFrameSync *fs)
Examine the frames in the filter's input and try to produce output.
Definition: framesync.c:341
ff_framesync_dualinput_get_writable
int ff_framesync_dualinput_get_writable(FFFrameSync *fs, AVFrame **f0, AVFrame **f1)
Same as ff_framesync_dualinput_get(), but make sure that f0 is writable.
Definition: framesync.c:396
drawutils.h
AV_PIX_FMT_YUVA422P
@ AV_PIX_FMT_YUVA422P
planar YUV 4:2:2 24bpp, (1 Cr & Cb sample per 2x1 Y & A samples)
Definition: pixfmt.h:166
activate
static int activate(AVFilterContext *ctx)
Definition: vf_alphamerge.c:151
AlphaMergeContext::is_packed_rgb
int is_packed_rgb
Definition: vf_alphamerge.c:44