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 "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 
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:295
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[]
FF_FILTER_FORWARD_STATUS(inlink, outlink)
static int activate(AVFilterContext *ctx)
return FFERROR_NOT_READY
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
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
the definition of that something depends on the semantic of the filter The callback must examine the status of the filter s links and proceed accordingly The status of output links is stored in the status_in and status_out fields and tested by the ff_outlink_frame_wanted() function.If this function returns true
#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:353
#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)
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:122
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:439
static const AVFilterPad alphamerge_outputs[]
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
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:326
planar YUV 4:4:4 32bpp, (1 Cr & Cb sample per 1x1 Y & A samples)
Definition: pixfmt.h:177
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
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 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:309
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
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:353
#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
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
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
int * formats
list of media formats
Definition: formats.h:66