FFmpeg  4.3
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 "internal.h"
36 #include "video.h"
37 
38 enum { Y, U, V, A };
39 
40 typedef struct AlphaMergeContext {
41  const AVClass *class;
42 
48 
50 {
51  static const enum AVPixelFormat main_fmts[] = {
56  };
57  static const enum AVPixelFormat alpha_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
58  AVFilterFormats *main_formats = NULL, *alpha_formats = NULL;
59  int ret;
60 
61  if (!(main_formats = ff_make_format_list(main_fmts)) ||
62  !(alpha_formats = ff_make_format_list(alpha_fmts))) {
63  ret = AVERROR(ENOMEM);
64  goto fail;
65  }
66  if ((ret = ff_formats_ref(main_formats , &ctx->inputs[0]->out_formats)) < 0 ||
67  (ret = ff_formats_ref(alpha_formats, &ctx->inputs[1]->out_formats)) < 0 ||
68  (ret = ff_formats_ref(main_formats , &ctx->outputs[0]->in_formats)) < 0)
69  goto fail;
70  return 0;
71 fail:
72  if (main_formats)
73  av_freep(&main_formats->formats);
74  av_freep(&main_formats);
75  if (alpha_formats)
76  av_freep(&alpha_formats->formats);
77  av_freep(&alpha_formats);
78  return ret;
79 }
80 
81 static int config_input_main(AVFilterLink *inlink)
82 {
83  AlphaMergeContext *s = inlink->dst->priv;
84  s->is_packed_rgb =
85  ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0 &&
86  inlink->format != AV_PIX_FMT_GBRAP;
87  return 0;
88 }
89 
90 static int config_output(AVFilterLink *outlink)
91 {
92  AVFilterContext *ctx = outlink->src;
93  AVFilterLink *mainlink = ctx->inputs[0];
94  AVFilterLink *alphalink = ctx->inputs[1];
95  if (mainlink->w != alphalink->w || mainlink->h != alphalink->h) {
96  av_log(ctx, AV_LOG_ERROR,
97  "Input frame sizes do not match (%dx%d vs %dx%d).\n",
98  mainlink->w, mainlink->h,
99  alphalink->w, alphalink->h);
100  return AVERROR(EINVAL);
101  }
102 
103  outlink->w = mainlink->w;
104  outlink->h = mainlink->h;
105  outlink->time_base = mainlink->time_base;
106  outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
107  outlink->frame_rate = mainlink->frame_rate;
108  return 0;
109 }
110 
112  AVFrame *main_buf,
113  AVFrame *alpha_buf)
114 {
115  AlphaMergeContext *s = ctx->priv;
116  int h = main_buf->height;
117 
118  if (s->is_packed_rgb) {
119  int x, y;
120  uint8_t *pin, *pout;
121  for (y = 0; y < h; y++) {
122  pin = alpha_buf->data[0] + y * alpha_buf->linesize[0];
123  pout = main_buf->data[0] + y * main_buf->linesize[0] + s->rgba_map[A];
124  for (x = 0; x < main_buf->width; x++) {
125  *pout = *pin;
126  pin += 1;
127  pout += 4;
128  }
129  }
130  } else {
131  const int main_linesize = main_buf->linesize[A];
132  const int alpha_linesize = alpha_buf->linesize[Y];
133  av_image_copy_plane(main_buf->data[A], main_linesize,
134  alpha_buf->data[Y], alpha_linesize,
135  FFMIN(main_linesize, alpha_linesize), alpha_buf->height);
136  }
137 }
138 
140 {
141  AVFilterLink *outlink = ctx->outputs[0];
142  AlphaMergeContext *s = ctx->priv;
143  int ret;
144 
145  FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, ctx);
146 
147  if (!s->main_frame) {
148  ret = ff_inlink_consume_frame(ctx->inputs[0], &s->main_frame);
149  if (ret < 0)
150  return ret;
151  }
152 
153  if (!s->alpha_frame) {
154  ret = ff_inlink_consume_frame(ctx->inputs[1], &s->alpha_frame);
155  if (ret < 0)
156  return ret;
157  }
158 
159  if (s->main_frame && s->alpha_frame) {
160  if (!ctx->is_disabled)
161  draw_frame(ctx, s->main_frame, s->alpha_frame);
162  ret = ff_filter_frame(outlink, s->main_frame);
164  s->main_frame = NULL;
165  return ret;
166  }
167 
168  FF_FILTER_FORWARD_STATUS(ctx->inputs[0], outlink);
169  FF_FILTER_FORWARD_STATUS(ctx->inputs[1], outlink);
170 
171  if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
172  !ff_outlink_get_status(ctx->inputs[0]) &&
173  !s->main_frame) {
175  return 0;
176  }
177 
178  if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
179  !ff_outlink_get_status(ctx->inputs[1]) &&
180  !s->alpha_frame) {
182  return 0;
183  }
184 
185  return FFERROR_NOT_READY;
186 }
187 
188 static const AVFilterPad alphamerge_inputs[] = {
189  {
190  .name = "main",
191  .type = AVMEDIA_TYPE_VIDEO,
192  .config_props = config_input_main,
193  .needs_writable = 1,
194  },{
195  .name = "alpha",
196  .type = AVMEDIA_TYPE_VIDEO,
197  },
198  { NULL }
199 };
200 
201 static const AVFilterPad alphamerge_outputs[] = {
202  {
203  .name = "default",
204  .type = AVMEDIA_TYPE_VIDEO,
205  .config_props = config_output,
206  },
207  { NULL }
208 };
209 
210 static const AVOption alphamerge_options[] = {
211  { NULL }
212 };
213 
214 AVFILTER_DEFINE_CLASS(alphamerge);
215 
217  .name = "alphamerge",
218  .description = NULL_IF_CONFIG_SMALL("Copy the luma value of the second "
219  "input into the alpha channel of the first input."),
220  .priv_size = sizeof(AlphaMergeContext),
221  .priv_class = &alphamerge_class,
223  .inputs = alphamerge_inputs,
224  .outputs = alphamerge_outputs,
225  .activate = activate,
227 };
int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe)
Take a frame from the link&#39;s FIFO and update the link&#39;s stats.
Definition: avfilter.c:1476
#define NULL
Definition: coverity.c:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:300
AVOption.
Definition: opt.h:246
misc image utilities
#define FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, filter)
Forward the status on an output link to all input links.
Definition: filters.h:212
Main libavfilter public API header.
static const AVFilterPad alphamerge_inputs[]
#define FFERROR_NOT_READY
Filters implementation helper functions.
Definition: filters.h:34
static int activate(AVFilterContext *ctx)
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:385
void ff_inlink_request_frame(AVFilterLink *link)
Mark that a frame is wanted on the link.
Definition: avfilter.c:1602
static int ff_outlink_frame_wanted(AVFilterLink *link)
Test if a frame is wanted on an output link.
Definition: filters.h:172
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
const char * name
Pad name.
Definition: internal.h:60
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:346
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1075
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:101
AVFILTER_DEFINE_CLASS(alphamerge)
uint8_t
AVOptions.
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:94
AVFrame * main_frame
Definition: vf_alphamerge.c:45
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:54
static int config_input_main(AVFilterLink *inlink)
Definition: vf_alphamerge.c:81
planar YUV 4:2:2 24bpp, (1 Cr & Cb sample per 2x1 Y & A samples)
Definition: pixfmt.h:176
int width
Definition: frame.h:358
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static void draw_frame(AVFilterContext *ctx, AVFrame *main_buf, AVFrame *alpha_buf)
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
void * priv
private data for use by the filter
Definition: avfilter.h:353
static const AVOption alphamerge_options[]
static int query_formats(AVFilterContext *ctx)
Definition: vf_alphamerge.c:49
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:92
#define fail()
Definition: checkasm.h:123
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:93
#define FFMIN(a, b)
Definition: common.h:96
int ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:470
static const AVFilterPad alphamerge_outputs[]
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
int ff_fill_rgba_map(uint8_t *rgba_map, enum AVPixelFormat pix_fmt)
Definition: drawutils.c:35
misc drawing utilities
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:331
planar YUV 4:4:4 32bpp, (1 Cr & Cb sample per 1x1 Y & A samples)
Definition: pixfmt.h:177
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
int ff_outlink_get_status(AVFilterLink *link)
Get the status on an output link.
Definition: avfilter.c:1625
const char * name
Filter name.
Definition: avfilter.h:148
#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:133
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
#define FF_FILTER_FORWARD_STATUS(inlink, outlink)
Acknowledge the status on an input link and forward it to an output link.
Definition: filters.h:226
#define flags(name, subs,...)
Definition: cbs_av1.c:564
static int config_output(AVFilterLink *outlink)
Definition: vf_alphamerge.c:90
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:314
Y , 8bpp.
Definition: pixfmt.h:74
planar GBRA 4:4:4:4 32bpp
Definition: pixfmt.h:215
AVFilter ff_vf_alphamerge
AVFrame * alpha_frame
Definition: vf_alphamerge.c:46
pixel format definitions
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
int height
Definition: frame.h:358
#define av_freep(p)
uint8_t rgba_map[4]
Definition: vf_alphamerge.c:44
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:338
internal API functions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
int * formats
list of media formats
Definition: formats.h:66