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caca.c
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1 /*
2  * Copyright (c) 2012 Paul B Mahol
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 #include <caca.h>
22 #include "libavutil/opt.h"
23 #include "libavutil/pixdesc.h"
24 #include "avdevice.h"
25 
26 typedef struct CACAContext {
27  AVClass *class;
29  char *window_title;
31 
32  caca_canvas_t *canvas;
33  caca_display_t *display;
34  caca_dither_t *dither;
35 
37  char *charset, *color;
38  char *driver;
39 
40  char *list_dither;
42 } CACAContext;
43 
45 {
46  CACAContext *c = s->priv_data;
47 
49 
50  if (c->display) {
51  caca_free_display(c->display);
52  c->display = NULL;
53  }
54  if (c->dither) {
55  caca_free_dither(c->dither);
56  c->dither = NULL;
57  }
58  if (c->canvas) {
59  caca_free_canvas(c->canvas);
60  c->canvas = NULL;
61  }
62  return 0;
63 }
64 
65 static void list_drivers(CACAContext *c)
66 {
67  const char *const *drivers = caca_get_display_driver_list();
68  int i;
69 
70  av_log(c->ctx, AV_LOG_INFO, "Available drivers:\n");
71  for (i = 0; drivers[i]; i += 2)
72  av_log(c->ctx, AV_LOG_INFO, "%s : %s\n", drivers[i], drivers[i + 1]);
73 }
74 
75 #define DEFINE_LIST_DITHER(thing, thing_str) \
76 static void list_dither_## thing(CACAContext *c) \
77 { \
78  const char *const *thing = caca_get_dither_## thing ##_list(c->dither); \
79  int i; \
80  \
81  av_log(c->ctx, AV_LOG_INFO, "Available %s:\n", thing_str); \
82  for (i = 0; thing[i]; i += 2) \
83  av_log(c->ctx, AV_LOG_INFO, "%s : %s\n", thing[i], thing[i + 1]); \
84 }
85 
86 DEFINE_LIST_DITHER(color, "colors");
87 DEFINE_LIST_DITHER(charset, "charsets");
88 DEFINE_LIST_DITHER(algorithm, "algorithms");
89 DEFINE_LIST_DITHER(antialias, "antialias");
90 
92 {
93  CACAContext *c = s->priv_data;
94  AVStream *st = s->streams[0];
95  AVCodecContext *encctx = st->codec;
96  int ret, bpp;
97 
98  c->ctx = s;
99  if (c->list_drivers) {
100  list_drivers(c);
101  return AVERROR_EXIT;
102  }
103  if (c->list_dither) {
104  if (!strcmp(c->list_dither, "colors")) {
105  list_dither_color(c);
106  } else if (!strcmp(c->list_dither, "charsets")) {
107  list_dither_charset(c);
108  } else if (!strcmp(c->list_dither, "algorithms")) {
109  list_dither_algorithm(c);
110  } else if (!strcmp(c->list_dither, "antialiases")) {
111  list_dither_antialias(c);
112  } else {
113  av_log(s, AV_LOG_ERROR,
114  "Invalid argument '%s', for 'list_dither' option\n"
115  "Argument must be one of 'algorithms, 'antialiases', 'charsets', 'colors'\n",
116  c->list_dither);
117  return AVERROR(EINVAL);
118  }
119  return AVERROR_EXIT;
120  }
121 
122  if ( s->nb_streams > 1
123  || encctx->codec_type != AVMEDIA_TYPE_VIDEO
124  || encctx->codec_id != AV_CODEC_ID_RAWVIDEO) {
125  av_log(s, AV_LOG_ERROR, "Only supports one rawvideo stream\n");
126  return AVERROR(EINVAL);
127  }
128 
129  if (encctx->pix_fmt != AV_PIX_FMT_RGB24) {
130  av_log(s, AV_LOG_ERROR,
131  "Unsupported pixel format '%s', choose rgb24\n",
132  av_get_pix_fmt_name(encctx->pix_fmt));
133  return AVERROR(EINVAL);
134  }
135 
136  c->canvas = caca_create_canvas(c->window_width, c->window_height);
137  if (!c->canvas) {
138  av_log(s, AV_LOG_ERROR, "Failed to create canvas\n");
139  ret = AVERROR(errno);
140  goto fail;
141  }
142 
144  c->dither = caca_create_dither(bpp, encctx->width, encctx->height,
145  bpp / 8 * encctx->width,
146  0x0000ff, 0x00ff00, 0xff0000, 0);
147  if (!c->dither) {
148  av_log(s, AV_LOG_ERROR, "Failed to create dither\n");
149  ret = AVERROR(errno);
150  goto fail;
151  }
152 
153 #define CHECK_DITHER_OPT(opt) \
154  if (caca_set_dither_##opt(c->dither, c->opt) < 0) { \
155  ret = AVERROR(errno); \
156  av_log(s, AV_LOG_ERROR, "Failed to set value '%s' for option '%s'\n", \
157  c->opt, #opt); \
158  goto fail; \
159  }
160  CHECK_DITHER_OPT(algorithm);
161  CHECK_DITHER_OPT(antialias);
162  CHECK_DITHER_OPT(charset);
164 
165  c->display = caca_create_display_with_driver(c->canvas, c->driver);
166  if (!c->display) {
167  av_log(s, AV_LOG_ERROR, "Failed to create display\n");
168  list_drivers(c);
169  ret = AVERROR(errno);
170  goto fail;
171  }
172 
173  if (!c->window_width || !c->window_height) {
174  c->window_width = caca_get_canvas_width(c->canvas);
175  c->window_height = caca_get_canvas_height(c->canvas);
176  }
177 
178  if (!c->window_title)
180  caca_set_display_title(c->display, c->window_title);
181  caca_set_display_time(c->display, av_rescale_q(1, st->codec->time_base, AV_TIME_BASE_Q));
182 
183  return 0;
184 
185 fail:
187  return ret;
188 }
189 
191 {
192  CACAContext *c = s->priv_data;
193 
194  caca_dither_bitmap(c->canvas, 0, 0, c->window_width, c->window_height, c->dither, pkt->data);
195  caca_refresh_display(c->display);
196 
197  return 0;
198 }
199 
200 #define OFFSET(x) offsetof(CACAContext,x)
201 #define ENC AV_OPT_FLAG_ENCODING_PARAM
202 
203 static const AVOption options[] = {
204  { "window_size", "set window forced size", OFFSET(window_width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL }, 0, 0, ENC},
205  { "window_title", "set window title", OFFSET(window_title), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, ENC },
206  { "driver", "set display driver", OFFSET(driver), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, ENC },
207  { "algorithm", "set dithering algorithm", OFFSET(algorithm), AV_OPT_TYPE_STRING, {.str = "default" }, 0, 0, ENC },
208  { "antialias", "set antialias method", OFFSET(antialias), AV_OPT_TYPE_STRING, {.str = "default" }, 0, 0, ENC },
209  { "charset", "set charset used to render output", OFFSET(charset), AV_OPT_TYPE_STRING, {.str = "default" }, 0, 0, ENC },
210  { "color", "set color used to render output", OFFSET(color), AV_OPT_TYPE_STRING, {.str = "default" }, 0, 0, ENC },
211  { "list_drivers", "list available drivers", OFFSET(list_drivers), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, ENC, "list_drivers" },
212  { "true", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 1}, 0, 0, ENC, "list_drivers" },
213  { "false", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0}, 0, 0, ENC, "list_drivers" },
214  { "list_dither", "list available dither options", OFFSET(list_dither), AV_OPT_TYPE_STRING, {.dbl=0}, 0, 1, ENC, "list_dither" },
215  { "algorithms", NULL, 0, AV_OPT_TYPE_CONST, {.str = "algorithms"}, 0, 0, ENC, "list_dither" },
216  { "antialiases", NULL, 0, AV_OPT_TYPE_CONST, {.str = "antialiases"},0, 0, ENC, "list_dither" },
217  { "charsets", NULL, 0, AV_OPT_TYPE_CONST, {.str = "charsets"}, 0, 0, ENC, "list_dither" },
218  { "colors", NULL, 0, AV_OPT_TYPE_CONST, {.str = "colors"}, 0, 0, ENC, "list_dither" },
219  { NULL },
220 };
221 
222 static const AVClass caca_class = {
223  .class_name = "caca_outdev",
224  .item_name = av_default_item_name,
225  .option = options,
226  .version = LIBAVUTIL_VERSION_INT,
227 };
228 
230  .name = "caca",
231  .long_name = NULL_IF_CONFIG_SMALL("caca (color ASCII art) output device"),
232  .priv_data_size = sizeof(CACAContext),
233  .audio_codec = AV_CODEC_ID_NONE,
234  .video_codec = AV_CODEC_ID_RAWVIDEO,
238  .flags = AVFMT_NOFILE,
239  .priv_class = &caca_class,
240 };