ffmpeg/libavdevice/sdl.c

   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 <SDL_thread.h>
  28
  29 #include "libavutil/avstring.h"
  30 #include "libavutil/opt.h"
  31 #include "libavutil/parseutils.h"
  32 #include "libavutil/pixdesc.h"
  33 #include "libavutil/time.h"
  34 #include "avdevice.h"
  35
  36 typedef struct {
  37     AVClass *class;
  38     SDL_Surface *surface;
  39     SDL_Overlay *overlay;
  40     char *window_title;
  41     char *icon_title;
  42     int window_width,  window_height;  /**< size of the window */
  43     int window_fullscreen;
  44
  45     SDL_Rect overlay_rect;
  46     int overlay_fmt;
  47
  48     int sdl_was_already_inited;
  49     SDL_Thread *event_thread;
  50     SDL_mutex *mutex;
  51     SDL_cond *init_cond;
  52     int init_ret; /* return code used to signal initialization errors */
  53     int inited;
  54     int quit;
  55 } SDLContext;
  56
  57 static const struct sdl_overlay_pix_fmt_entry {
  58     enum AVPixelFormat pix_fmt; int overlay_fmt;
  59 } sdl_overlay_pix_fmt_map[] = {
  60     { AV_PIX_FMT_YUV420P, SDL_IYUV_OVERLAY },
  61     { AV_PIX_FMT_YUYV422, SDL_YUY2_OVERLAY },
  62     { AV_PIX_FMT_UYVY422, SDL_UYVY_OVERLAY },
  63     { AV_PIX_FMT_NONE,    0                },
  64 };
  65
  66 static int sdl_write_trailer(AVFormatContext *s)
  67 {
  68     SDLContext *sdl = s->priv_data;
  69
  70     sdl->quit = 1;
  71
  72     if (sdl->overlay)
  73         SDL_FreeYUVOverlay(sdl->overlay);
  74     sdl->overlay = NULL;
  75     if (sdl->event_thread)
  76         SDL_WaitThread(sdl->event_thread, NULL);
  77     sdl->event_thread = NULL;
  78     if (sdl->mutex)
  79         SDL_DestroyMutex(sdl->mutex);
  80     sdl->mutex = NULL;
  81     if (sdl->init_cond)
  82         SDL_DestroyCond(sdl->init_cond);
  83     sdl->init_cond = NULL;
  84
  85     if (!sdl->sdl_was_already_inited)
  86         SDL_Quit();
  87
  88     return 0;
  89 }
  90
  91 static void compute_overlay_rect(AVFormatContext *s)
  92 {
  93     AVRational sar, dar; /* sample and display aspect ratios */
  94     SDLContext *sdl = s->priv_data;
  95     AVStream *st = s->streams[0];
  96     AVCodecContext *encctx = st->codec;
  97     SDL_Rect *overlay_rect = &sdl->overlay_rect;
  98
  99     /* compute overlay width and height from the codec context information */
 100     sar = st->sample_aspect_ratio.num ? st->sample_aspect_ratio : (AVRational){ 1, 1 };
 101     dar = av_mul_q(sar, (AVRational){ encctx->width, encctx->height });
 102
 103     /* we suppose the screen has a 1/1 sample aspect ratio */
 104     if (sdl->window_width && sdl->window_height) {
 105         /* fit in the window */
 106         if (av_cmp_q(dar, (AVRational){ sdl->window_width, sdl->window_height }) > 0) {
 107             /* fit in width */
 108             overlay_rect->w = sdl->window_width;
 109             overlay_rect->h = av_rescale(overlay_rect->w, dar.den, dar.num);
 110         } else {
 111             /* fit in height */
 112             overlay_rect->h = sdl->window_height;
 113             overlay_rect->w = av_rescale(overlay_rect->h, dar.num, dar.den);
 114         }
 115     } else {
 116         if (sar.num > sar.den) {
 117             overlay_rect->w = encctx->width;
 118             overlay_rect->h = av_rescale(overlay_rect->w, dar.den, dar.num);
 119         } else {
 120             overlay_rect->h = encctx->height;
 121             overlay_rect->w = av_rescale(overlay_rect->h, dar.num, dar.den);
 122         }
 123         sdl->window_width  = overlay_rect->w;
 124         sdl->window_height = overlay_rect->h;
 125     }
 126
 127     overlay_rect->x = (sdl->window_width  - overlay_rect->w) / 2;
 128     overlay_rect->y = (sdl->window_height - overlay_rect->h) / 2;
 129 }
 130
 131 #define SDL_BASE_FLAGS (SDL_SWSURFACE|SDL_RESIZABLE)
 132
 133 static int event_thread(void *arg)
 134 {
 135     AVFormatContext *s = arg;
 136     SDLContext *sdl = s->priv_data;
 137     int flags = SDL_BASE_FLAGS | (sdl->window_fullscreen ? SDL_FULLSCREEN : 0);
 138     AVStream *st = s->streams[0];
 139     AVCodecContext *encctx = st->codec;
 140
 141     /* initialization */
 142     if (SDL_Init(SDL_INIT_VIDEO) != 0) {
 143         av_log(s, AV_LOG_ERROR, "Unable to initialize SDL: %s\n", SDL_GetError());
 144         sdl->init_ret = AVERROR(EINVAL);
 145         goto init_end;
 146     }
 147
 148     SDL_WM_SetCaption(sdl->window_title, sdl->icon_title);
 149     sdl->surface = SDL_SetVideoMode(sdl->window_width, sdl->window_height,
 150                                     24, flags);
 151     if (!sdl->surface) {
 152         av_log(sdl, AV_LOG_ERROR, "Unable to set video mode: %s\n", SDL_GetError());
 153         sdl->init_ret = AVERROR(EINVAL);
 154         goto init_end;
 155     }
 156
 157     sdl->overlay = SDL_CreateYUVOverlay(encctx->width, encctx->height,
 158                                         sdl->overlay_fmt, sdl->surface);
 159     if (!sdl->overlay || sdl->overlay->pitches[0] < encctx->width) {
 160         av_log(s, AV_LOG_ERROR,
 161                "SDL does not support an overlay with size of %dx%d pixels\n",
 162                encctx->width, encctx->height);
 163         sdl->init_ret = AVERROR(EINVAL);
 164         goto init_end;
 165     }
 166
 167     sdl->init_ret = 0;
 168     av_log(s, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s -> w:%d h:%d\n",
 169            encctx->width, encctx->height, av_get_pix_fmt_name(encctx->pix_fmt),
 170            sdl->overlay_rect.w, sdl->overlay_rect.h);
 171
 172 init_end:
 173     SDL_LockMutex(sdl->mutex);
 174     sdl->inited = 1;
 175     SDL_UnlockMutex(sdl->mutex);
 176     SDL_CondSignal(sdl->init_cond);
 177
 178     if (sdl->init_ret < 0)
 179         return sdl->init_ret;
 180
 181     /* event loop */
 182     while (!sdl->quit) {
 183         int ret;
 184         SDL_Event event;
 185         SDL_PumpEvents();
 186         ret = SDL_PeepEvents(&event, 1, SDL_GETEVENT, SDL_ALLEVENTS);
 187         if (ret < 0) {
 188             av_log(s, AV_LOG_ERROR, "Error when getting SDL event: %s\n", SDL_GetError());
 189             continue;
 190         }
 191         if (ret == 0) {
 192             SDL_Delay(10);
 193             continue;
 194         }
 195
 196         switch (event.type) {
 197         case SDL_KEYDOWN:
 198             switch (event.key.keysym.sym) {
 199             case SDLK_ESCAPE:
 200             case SDLK_q:
 201                 sdl->quit = 1;
 202                 break;
 203             }
 204             break;
 205         case SDL_QUIT:
 206             sdl->quit = 1;
 207             break;
 208
 209         case SDL_VIDEORESIZE:
 210             sdl->window_width  = event.resize.w;
 211             sdl->window_height = event.resize.h;
 212
 213             SDL_LockMutex(sdl->mutex);
 214             sdl->surface = SDL_SetVideoMode(sdl->window_width, sdl->window_height, 24, SDL_BASE_FLAGS);
 215             if (!sdl->surface) {
 216                 av_log(s, AV_LOG_ERROR, "Failed to set SDL video mode: %s\n", SDL_GetError());
 217                 sdl->quit = 1;
 218             } else {
 219                 compute_overlay_rect(s);
 220             }
 221             SDL_UnlockMutex(sdl->mutex);
 222             break;
 223
 224         default:
 225             break;
 226         }
 227     }
 228
 229     return 0;
 230 }
 231
 232 static int sdl_write_header(AVFormatContext *s)
 233 {
 234     SDLContext *sdl = s->priv_data;
 235     AVStream *st = s->streams[0];
 236     AVCodecContext *encctx = st->codec;
 237     int i, ret;
 238
 239     if (!sdl->window_title)
 240         sdl->window_title = av_strdup(s->filename);
 241     if (!sdl->icon_title)
 242         sdl->icon_title = av_strdup(sdl->window_title);
 243
 244     if (SDL_WasInit(SDL_INIT_VIDEO)) {
 245         av_log(s, AV_LOG_ERROR,
 246                "SDL video subsystem was already inited, aborting\n");
 247         sdl->sdl_was_already_inited = 1;
 248         ret = AVERROR(EINVAL);
 249         goto fail;
 250     }
 251
 252     if (   s->nb_streams > 1
 253         || encctx->codec_type != AVMEDIA_TYPE_VIDEO
 254         || encctx->codec_id   != AV_CODEC_ID_RAWVIDEO) {
 255         av_log(s, AV_LOG_ERROR, "Only supports one rawvideo stream\n");
 256         ret = AVERROR(EINVAL);
 257         goto fail;
 258     }
 259
 260     for (i = 0; sdl_overlay_pix_fmt_map[i].pix_fmt != AV_PIX_FMT_NONE; i++) {
 261         if (sdl_overlay_pix_fmt_map[i].pix_fmt == encctx->pix_fmt) {
 262             sdl->overlay_fmt = sdl_overlay_pix_fmt_map[i].overlay_fmt;
 263             break;
 264         }
 265     }
 266
 267     if (!sdl->overlay_fmt) {
 268         av_log(s, AV_LOG_ERROR,
 269                "Unsupported pixel format '%s', choose one of yuv420p, yuyv422, or uyvy422\n",
 270                av_get_pix_fmt_name(encctx->pix_fmt));
 271         ret = AVERROR(EINVAL);
 272         goto fail;
 273     }
 274
 275     /* compute overlay width and height from the codec context information */
 276     compute_overlay_rect(s);
 277
 278     sdl->init_cond = SDL_CreateCond();
 279     if (!sdl->init_cond) {
 280         av_log(s, AV_LOG_ERROR, "Could not create SDL condition variable: %s\n", SDL_GetError());
 281         ret = AVERROR_EXTERNAL;
 282         goto fail;
 283     }
 284     sdl->mutex = SDL_CreateMutex();
 285     if (!sdl->mutex) {
 286         av_log(s, AV_LOG_ERROR, "Could not create SDL mutex: %s\n", SDL_GetError());
 287         ret = AVERROR_EXTERNAL;
 288         goto fail;
 289     }
 290     sdl->event_thread = SDL_CreateThread(event_thread, s);
 291     if (!sdl->event_thread) {
 292         av_log(s, AV_LOG_ERROR, "Could not create SDL event thread: %s\n", SDL_GetError());
 293         ret = AVERROR_EXTERNAL;
 294         goto fail;
 295     }
 296
 297     /* wait until the video system has been inited */
 298     SDL_LockMutex(sdl->mutex);
 299     while (!sdl->inited) {
 300         SDL_CondWait(sdl->init_cond, sdl->mutex);
 301     }
 302     SDL_UnlockMutex(sdl->mutex);
 303     if (sdl->init_ret < 0) {
 304         ret = sdl->init_ret;
 305         goto fail;
 306     }
 307     return 0;
 308
 309 fail:
 310     sdl_write_trailer(s);
 311     return ret;
 312 }
 313
 314 static int sdl_write_packet(AVFormatContext *s, AVPacket *pkt)
 315 {
 316     SDLContext *sdl = s->priv_data;
 317     AVCodecContext *encctx = s->streams[0]->codec;
 318     AVPicture pict;
 319     int i;
 320
 321     if (sdl->quit) {
 322         sdl_write_trailer(s);
 323         return AVERROR(EIO);
 324     }
 325     avpicture_fill(&pict, pkt->data, encctx->pix_fmt, encctx->width, encctx->height);
 326
 327     SDL_LockMutex(sdl->mutex);
 328     SDL_FillRect(sdl->surface, &sdl->surface->clip_rect,
 329                  SDL_MapRGB(sdl->surface->format, 0, 0, 0));
 330     SDL_LockYUVOverlay(sdl->overlay);
 331     for (i = 0; i < 3; i++) {
 332         sdl->overlay->pixels [i] = pict.data    [i];
 333         sdl->overlay->pitches[i] = pict.linesize[i];
 334     }
 335     SDL_DisplayYUVOverlay(sdl->overlay, &sdl->overlay_rect);
 336     SDL_UnlockYUVOverlay(sdl->overlay);
 337
 338     SDL_UpdateRect(sdl->surface,
 339                    sdl->overlay_rect.x, sdl->overlay_rect.y,
 340                    sdl->overlay_rect.w, sdl->overlay_rect.h);
 341     SDL_UnlockMutex(sdl->mutex);
 342
 343     return 0;
 344 }
 345
 346 #define OFFSET(x) offsetof(SDLContext,x)
 347
 348 static const AVOption options[] = {
 349     { "window_title", "set SDL window title",           OFFSET(window_title), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
 350     { "icon_title",   "set SDL iconified window title", OFFSET(icon_title)  , AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
 351     { "window_size",  "set SDL window forced size",     OFFSET(window_width), AV_OPT_TYPE_IMAGE_SIZE, { .str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
 352     { "window_fullscreen", "set SDL window fullscreen", OFFSET(window_fullscreen), AV_OPT_TYPE_INT, { .i64 = 0 }, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
 353     { NULL },
 354 };
 355
 356 static const AVClass sdl_class = {
 357     .class_name = "sdl outdev",
 358     .item_name  = av_default_item_name,
 359     .option     = options,
 360     .version    = LIBAVUTIL_VERSION_INT,
 361     .category   = AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT,
 362 };
 363
 364 AVOutputFormat ff_sdl_muxer = {
 365     .name           = "sdl",
 366     .long_name      = NULL_IF_CONFIG_SMALL("SDL output device"),
 367     .priv_data_size = sizeof(SDLContext),
 368     .audio_codec    = AV_CODEC_ID_NONE,
 369     .video_codec    = AV_CODEC_ID_RAWVIDEO,
 370     .write_header   = sdl_write_header,
 371     .write_packet   = sdl_write_packet,
 372     .write_trailer  = sdl_write_trailer,
 373     .flags          = AVFMT_NOFILE | AVFMT_VARIABLE_FPS | AVFMT_NOTIMESTAMPS,
 374     .priv_class     = &sdl_class,
 375 };