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sdl.c
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1 /*
2  * Copyright (c) 2011 Stefano Sabatini
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  * libSDL output device
24  */
25 
26 #include <SDL.h>
27 #include "libavutil/avstring.h"
28 #include "libavutil/opt.h"
29 #include "libavutil/parseutils.h"
30 #include "libavutil/pixdesc.h"
31 #include "avdevice.h"
32 
33 typedef struct {
34  AVClass *class;
35  SDL_Surface *surface;
36  SDL_Overlay *overlay;
37  char *window_title;
38  char *icon_title;
39  int window_width, window_height; /**< size of the window */
41  int overlay_width, overlay_height; /**< size of the video in the window */
42  int overlay_x, overlay_y;
45 } SDLContext;
46 
47 static const struct sdl_overlay_pix_fmt_entry {
50  { AV_PIX_FMT_YUV420P, SDL_IYUV_OVERLAY },
51  { AV_PIX_FMT_YUYV422, SDL_YUY2_OVERLAY },
52  { AV_PIX_FMT_UYVY422, SDL_UYVY_OVERLAY },
53  { AV_PIX_FMT_NONE, 0 },
54 };
55 
57 {
58  SDLContext *sdl = s->priv_data;
59 
60  av_freep(&sdl->window_title);
61  av_freep(&sdl->icon_title);
62 
63  if (sdl->overlay) {
64  SDL_FreeYUVOverlay(sdl->overlay);
65  sdl->overlay = NULL;
66  }
67  if (!sdl->sdl_was_already_inited)
68  SDL_Quit();
69 
70  return 0;
71 }
72 
74 {
75  SDLContext *sdl = s->priv_data;
76  AVStream *st = s->streams[0];
77  AVCodecContext *encctx = st->codec;
78  AVRational sar, dar; /* sample and display aspect ratios */
79  int i, ret;
80  int flags = SDL_SWSURFACE | sdl->window_fullscreen ? SDL_FULLSCREEN : 0;
81 
82  if (!sdl->window_title)
83  sdl->window_title = av_strdup(s->filename);
84  if (!sdl->icon_title)
85  sdl->icon_title = av_strdup(sdl->window_title);
86 
87  if (SDL_WasInit(SDL_INIT_VIDEO)) {
89  "SDL video subsystem was already inited, aborting\n");
90  sdl->sdl_was_already_inited = 1;
91  ret = AVERROR(EINVAL);
92  goto fail;
93  }
94 
95  if (SDL_Init(SDL_INIT_VIDEO) != 0) {
96  av_log(s, AV_LOG_ERROR, "Unable to initialize SDL: %s\n", SDL_GetError());
97  ret = AVERROR(EINVAL);
98  goto fail;
99  }
100 
101  if ( s->nb_streams > 1
102  || encctx->codec_type != AVMEDIA_TYPE_VIDEO
103  || encctx->codec_id != AV_CODEC_ID_RAWVIDEO) {
104  av_log(s, AV_LOG_ERROR, "Only supports one rawvideo stream\n");
105  ret = AVERROR(EINVAL);
106  goto fail;
107  }
108 
109  for (i = 0; sdl_overlay_pix_fmt_map[i].pix_fmt != AV_PIX_FMT_NONE; i++) {
110  if (sdl_overlay_pix_fmt_map[i].pix_fmt == encctx->pix_fmt) {
112  break;
113  }
114  }
115 
116  if (!sdl->overlay_fmt) {
117  av_log(s, AV_LOG_ERROR,
118  "Unsupported pixel format '%s', choose one of yuv420p, yuyv422, or uyvy422\n",
119  av_get_pix_fmt_name(encctx->pix_fmt));
120  ret = AVERROR(EINVAL);
121  goto fail;
122  }
123 
124  /* compute overlay width and height from the codec context information */
125  sar = st->sample_aspect_ratio.num ? st->sample_aspect_ratio : (AVRational){ 1, 1 };
126  dar = av_mul_q(sar, (AVRational){ encctx->width, encctx->height });
127 
128  /* we suppose the screen has a 1/1 sample aspect ratio */
129  if (sdl->window_width && sdl->window_height) {
130  /* fit in the window */
131  if (av_cmp_q(dar, (AVRational){ sdl->window_width, sdl->window_height }) > 0) {
132  /* fit in width */
133  sdl->overlay_width = sdl->window_width;
134  sdl->overlay_height = av_rescale(sdl->overlay_width, dar.den, dar.num);
135  } else {
136  /* fit in height */
137  sdl->overlay_height = sdl->window_height;
138  sdl->overlay_width = av_rescale(sdl->overlay_height, dar.num, dar.den);
139  }
140  } else {
141  if (sar.num > sar.den) {
142  sdl->overlay_width = encctx->width;
143  sdl->overlay_height = av_rescale(sdl->overlay_width, dar.den, dar.num);
144  } else {
145  sdl->overlay_height = encctx->height;
146  sdl->overlay_width = av_rescale(sdl->overlay_height, dar.num, dar.den);
147  }
148  sdl->window_width = sdl->overlay_width;
149  sdl->window_height = sdl->overlay_height;
150  }
151  sdl->overlay_x = (sdl->window_width - sdl->overlay_width ) / 2;
152  sdl->overlay_y = (sdl->window_height - sdl->overlay_height) / 2;
153 
154  SDL_WM_SetCaption(sdl->window_title, sdl->icon_title);
155  sdl->surface = SDL_SetVideoMode(sdl->window_width, sdl->window_height,
156  24, flags);
157  if (!sdl->surface) {
158  av_log(s, AV_LOG_ERROR, "Unable to set video mode: %s\n", SDL_GetError());
159  ret = AVERROR(EINVAL);
160  goto fail;
161  }
162 
163  sdl->overlay = SDL_CreateYUVOverlay(encctx->width, encctx->height,
164  sdl->overlay_fmt, sdl->surface);
165  if (!sdl->overlay || sdl->overlay->pitches[0] < encctx->width) {
166  av_log(s, AV_LOG_ERROR,
167  "SDL does not support an overlay with size of %dx%d pixels\n",
168  encctx->width, encctx->height);
169  ret = AVERROR(EINVAL);
170  goto fail;
171  }
172 
173  av_log(s, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s sar:%d/%d -> w:%d h:%d\n",
174  encctx->width, encctx->height, av_get_pix_fmt_name(encctx->pix_fmt), sar.num, sar.den,
175  sdl->overlay_width, sdl->overlay_height);
176  return 0;
177 
178 fail:
180  return ret;
181 }
182 
184 {
185  SDLContext *sdl = s->priv_data;
186  AVCodecContext *encctx = s->streams[0]->codec;
187  SDL_Rect rect = { sdl->overlay_x, sdl->overlay_y, sdl->overlay_width, sdl->overlay_height };
188  AVPicture pict;
189  int i;
190 
191  avpicture_fill(&pict, pkt->data, encctx->pix_fmt, encctx->width, encctx->height);
192 
193  SDL_FillRect(sdl->surface, &sdl->surface->clip_rect,
194  SDL_MapRGB(sdl->surface->format, 0, 0, 0));
195  SDL_LockYUVOverlay(sdl->overlay);
196  for (i = 0; i < 3; i++) {
197  sdl->overlay->pixels [i] = pict.data [i];
198  sdl->overlay->pitches[i] = pict.linesize[i];
199  }
200  SDL_DisplayYUVOverlay(sdl->overlay, &rect);
201  SDL_UnlockYUVOverlay(sdl->overlay);
202 
203  SDL_UpdateRect(sdl->surface, rect.x, rect.y, rect.w, rect.h);
204 
205  return 0;
206 }
207 
208 #define OFFSET(x) offsetof(SDLContext,x)
209 
210 static const AVOption options[] = {
211  { "window_title", "set SDL window title", OFFSET(window_title), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
212  { "icon_title", "set SDL iconified window title", OFFSET(icon_title) , AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
213  { "window_size", "set SDL window forced size", OFFSET(window_width), AV_OPT_TYPE_IMAGE_SIZE,{.str=NULL}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
214  { "window_fullscreen", "set SDL window fullscreen", OFFSET(window_fullscreen), AV_OPT_TYPE_INT,{.i64=0}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
215  { NULL },
216 };
217 
218 static const AVClass sdl_class = {
219  .class_name = "sdl outdev",
220  .item_name = av_default_item_name,
221  .option = options,
222  .version = LIBAVUTIL_VERSION_INT,
223 };
224 
226  .name = "sdl",
227  .long_name = NULL_IF_CONFIG_SMALL("SDL output device"),
228  .priv_data_size = sizeof(SDLContext),
229  .audio_codec = AV_CODEC_ID_NONE,
230  .video_codec = AV_CODEC_ID_RAWVIDEO,
235  .priv_class = &sdl_class,
236 };