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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 {
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; fmt < AV_PIX_FMT_NB; 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  ff_set_common_formats(ctx, pix_fmts);
59  return 0;
60 }
61 
62 static int config_props(AVFilterLink *inlink)
63 {
64  FlipContext *s = inlink->dst->priv;
65  const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
66  const int hsub = pix_desc->log2_chroma_w;
67  const int vsub = pix_desc->log2_chroma_h;
68 
69  av_image_fill_max_pixsteps(s->max_step, NULL, pix_desc);
70  s->planewidth[0] = s->planewidth[3] = inlink->w;
71  s->planewidth[1] = s->planewidth[2] = FF_CEIL_RSHIFT(inlink->w, hsub);
72  s->planeheight[0] = s->planeheight[3] = inlink->h;
73  s->planeheight[1] = s->planeheight[2] = FF_CEIL_RSHIFT(inlink->h, vsub);
74 
75  return 0;
76 }
77 
78 typedef struct ThreadData {
79  AVFrame *in, *out;
80 } ThreadData;
81 
82 static int filter_slice(AVFilterContext *ctx, void *arg, int job, int nb_jobs)
83 {
84  FlipContext *s = ctx->priv;
85  ThreadData *td = arg;
86  AVFrame *in = td->in;
87  AVFrame *out = td->out;
88  uint8_t *inrow, *outrow;
89  int i, j, plane, step;
90 
91  for (plane = 0; plane < 4 && in->data[plane] && in->linesize[plane]; plane++) {
92  const int width = s->planewidth[plane];
93  const int height = s->planeheight[plane];
94  const int start = (height * job ) / nb_jobs;
95  const int end = (height * (job+1)) / nb_jobs;
96 
97  step = s->max_step[plane];
98 
99  outrow = out->data[plane] + start * out->linesize[plane];
100  inrow = in ->data[plane] + start * in->linesize[plane] + (width - 1) * step;
101  for (i = start; i < end; i++) {
102  switch (step) {
103  case 1:
104  for (j = 0; j < width; j++)
105  outrow[j] = inrow[-j];
106  break;
107 
108  case 2:
109  {
110  uint16_t *outrow16 = (uint16_t *)outrow;
111  uint16_t * inrow16 = (uint16_t *) inrow;
112  for (j = 0; j < width; j++)
113  outrow16[j] = inrow16[-j];
114  }
115  break;
116 
117  case 3:
118  {
119  uint8_t *in = inrow;
120  uint8_t *out = outrow;
121  for (j = 0; j < width; j++, out += 3, in -= 3) {
122  int32_t v = AV_RB24(in);
123  AV_WB24(out, v);
124  }
125  }
126  break;
127 
128  case 4:
129  {
130  uint32_t *outrow32 = (uint32_t *)outrow;
131  uint32_t * inrow32 = (uint32_t *) inrow;
132  for (j = 0; j < width; j++)
133  outrow32[j] = inrow32[-j];
134  }
135  break;
136 
137  default:
138  for (j = 0; j < width; j++)
139  memcpy(outrow + j*step, inrow - j*step, step);
140  }
141 
142  inrow += in ->linesize[plane];
143  outrow += out->linesize[plane];
144  }
145  }
146 
147  return 0;
148 }
149 
150 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
151 {
152  AVFilterContext *ctx = inlink->dst;
153  AVFilterLink *outlink = ctx->outputs[0];
154  ThreadData td;
155  AVFrame *out;
156 
157  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
158  if (!out) {
159  av_frame_free(&in);
160  return AVERROR(ENOMEM);
161  }
162  av_frame_copy_props(out, in);
163 
164  /* copy palette if required */
166  memcpy(out->data[1], in->data[1], AVPALETTE_SIZE);
167 
168  td.in = in, td.out = out;
169  ctx->internal->execute(ctx, filter_slice, &td, NULL, FFMIN(outlink->h, ctx->graph->nb_threads));
170 
171  av_frame_free(&in);
172  return ff_filter_frame(outlink, out);
173 }
174 
176  {
177  .name = "default",
178  .type = AVMEDIA_TYPE_VIDEO,
179  .filter_frame = filter_frame,
180  .config_props = config_props,
181  },
182  { NULL }
183 };
184 
186  {
187  .name = "default",
188  .type = AVMEDIA_TYPE_VIDEO,
189  },
190  { NULL }
191 };
192 
194  .name = "hflip",
195  .description = NULL_IF_CONFIG_SMALL("Horizontally flip the input video."),
196  .priv_size = sizeof(FlipContext),
198  .inputs = avfilter_vf_hflip_inputs,
199  .outputs = avfilter_vf_hflip_outputs,
201 };