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vf_hflip.c
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1 /*
2  * Copyright (c) 2007 Benoit Fouet
3  * Copyright (c) 2010 Stefano Sabatini
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * horizontal flip filter
25  */
26 
27 #include <string.h>
28 
29 #include "avfilter.h"
30 #include "formats.h"
31 #include "internal.h"
32 #include "video.h"
33 #include "libavutil/pixdesc.h"
34 #include "libavutil/internal.h"
35 #include "libavutil/intreadwrite.h"
36 #include "libavutil/imgutils.h"
37 
38 typedef struct FlipContext {
39  int max_step[4]; ///< max pixel step for each plane, expressed as a number of bytes
40  int planewidth[4]; ///< width of each plane
41  int planeheight[4]; ///< height of each plane
42 } FlipContext;
43 
45 {
46  AVFilterFormats *pix_fmts = NULL;
47  int fmt;
48 
49  for (fmt = 0; av_pix_fmt_desc_get(fmt); fmt++) {
50  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(fmt);
51  if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL ||
53  (desc->log2_chroma_w != desc->log2_chroma_h &&
54  desc->comp[0].plane == desc->comp[1].plane)))
55  ff_add_format(&pix_fmts, fmt);
56  }
57 
58  return ff_set_common_formats(ctx, pix_fmts);
59 }
60 
61 static int config_props(AVFilterLink *inlink)
62 {
63  FlipContext *s = inlink->dst->priv;
64  const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
65  const int hsub = pix_desc->log2_chroma_w;
66  const int vsub = pix_desc->log2_chroma_h;
67 
69  s->planewidth[0] = s->planewidth[3] = inlink->w;
70  s->planewidth[1] = s->planewidth[2] = FF_CEIL_RSHIFT(inlink->w, hsub);
71  s->planeheight[0] = s->planeheight[3] = inlink->h;
72  s->planeheight[1] = s->planeheight[2] = FF_CEIL_RSHIFT(inlink->h, vsub);
73 
74  return 0;
75 }
76 
77 typedef struct ThreadData {
78  AVFrame *in, *out;
79 } ThreadData;
80 
81 static int filter_slice(AVFilterContext *ctx, void *arg, int job, int nb_jobs)
82 {
83  FlipContext *s = ctx->priv;
84  ThreadData *td = arg;
85  AVFrame *in = td->in;
86  AVFrame *out = td->out;
87  uint8_t *inrow, *outrow;
88  int i, j, plane, step;
89 
90  for (plane = 0; plane < 4 && in->data[plane] && in->linesize[plane]; plane++) {
91  const int width = s->planewidth[plane];
92  const int height = s->planeheight[plane];
93  const int start = (height * job ) / nb_jobs;
94  const int end = (height * (job+1)) / nb_jobs;
95 
96  step = s->max_step[plane];
97 
98  outrow = out->data[plane] + start * out->linesize[plane];
99  inrow = in ->data[plane] + start * in->linesize[plane] + (width - 1) * step;
100  for (i = start; i < end; i++) {
101  switch (step) {
102  case 1:
103  for (j = 0; j < width; j++)
104  outrow[j] = inrow[-j];
105  break;
106 
107  case 2:
108  {
109  uint16_t *outrow16 = (uint16_t *)outrow;
110  uint16_t * inrow16 = (uint16_t *) inrow;
111  for (j = 0; j < width; j++)
112  outrow16[j] = inrow16[-j];
113  }
114  break;
115 
116  case 3:
117  {
118  uint8_t *in = inrow;
119  uint8_t *out = outrow;
120  for (j = 0; j < width; j++, out += 3, in -= 3) {
121  int32_t v = AV_RB24(in);
122  AV_WB24(out, v);
123  }
124  }
125  break;
126 
127  case 4:
128  {
129  uint32_t *outrow32 = (uint32_t *)outrow;
130  uint32_t * inrow32 = (uint32_t *) inrow;
131  for (j = 0; j < width; j++)
132  outrow32[j] = inrow32[-j];
133  }
134  break;
135 
136  default:
137  for (j = 0; j < width; j++)
138  memcpy(outrow + j*step, inrow - j*step, step);
139  }
140 
141  inrow += in ->linesize[plane];
142  outrow += out->linesize[plane];
143  }
144  }
145 
146  return 0;
147 }
148 
149 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
150 {
151  AVFilterContext *ctx = inlink->dst;
152  AVFilterLink *outlink = ctx->outputs[0];
153  ThreadData td;
154  AVFrame *out;
155 
156  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
157  if (!out) {
158  av_frame_free(&in);
159  return AVERROR(ENOMEM);
160  }
161  av_frame_copy_props(out, in);
162 
163  /* copy palette if required */
165  memcpy(out->data[1], in->data[1], AVPALETTE_SIZE);
166 
167  td.in = in, td.out = out;
168  ctx->internal->execute(ctx, filter_slice, &td, NULL, FFMIN(outlink->h, ctx->graph->nb_threads));
169 
170  av_frame_free(&in);
171  return ff_filter_frame(outlink, out);
172 }
173 
175  {
176  .name = "default",
177  .type = AVMEDIA_TYPE_VIDEO,
178  .filter_frame = filter_frame,
179  .config_props = config_props,
180  },
181  { NULL }
182 };
183 
185  {
186  .name = "default",
187  .type = AVMEDIA_TYPE_VIDEO,
188  },
189  { NULL }
190 };
191 
193  .name = "hflip",
194  .description = NULL_IF_CONFIG_SMALL("Horizontally flip the input video."),
195  .priv_size = sizeof(FlipContext),
197  .inputs = avfilter_vf_hflip_inputs,
198  .outputs = avfilter_vf_hflip_outputs,
200 };