FFmpeg: libavdevice/sdl.c Source File

00001 /*
00002  * Copyright (c) 2011 Stefano Sabatini
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00026 #include <SDL.h>
00027 #include "libavutil/avstring.h"
00028 #include "libavutil/opt.h"
00029 #include "libavutil/parseutils.h"
00030 #include "libavutil/pixdesc.h"
00031 #include "avdevice.h"
00032 
00033 typedef struct {
00034     AVClass *class;
00035     SDL_Surface *surface;
00036     SDL_Overlay *overlay;
00037     char *window_title;
00038     char *icon_title;
00039     char *window_size;
00040     int window_width, window_height;
00041     int overlay_width, overlay_height;
00042     int overlay_fmt;
00043     int sdl_was_already_inited;
00044 } SDLContext;
00045 
00046 struct sdl_overlay_pix_fmt_entry {
00047     enum PixelFormat pix_fmt; int overlay_fmt;
00048 } sdl_overlay_pix_fmt_map[] = {
00049     { PIX_FMT_YUV420P, SDL_IYUV_OVERLAY },
00050     { PIX_FMT_YUYV422, SDL_YUY2_OVERLAY },
00051     { PIX_FMT_UYVY422, SDL_UYVY_OVERLAY },
00052     { PIX_FMT_NONE,    0                },
00053 };
00054 
00055 static int sdl_write_trailer(AVFormatContext *s)
00056 {
00057     SDLContext *sdl = s->priv_data;
00058 
00059     av_freep(&sdl->window_title);
00060     av_freep(&sdl->icon_title);
00061     av_freep(&sdl->window_size);
00062 
00063     if (sdl->overlay) {
00064         SDL_FreeYUVOverlay(sdl->overlay);
00065         sdl->overlay = NULL;
00066     }
00067     if (!sdl->sdl_was_already_inited)
00068         SDL_Quit();
00069 
00070     return 0;
00071 }
00072 
00073 static int sdl_write_header(AVFormatContext *s)
00074 {
00075     SDLContext *sdl = s->priv_data;
00076     AVStream *st = s->streams[0];
00077     AVCodecContext *encctx = st->codec;
00078     float sar, dar; /* sample and display aspect ratios */
00079     int i, ret;
00080 
00081     if (!sdl->window_title)
00082         sdl->window_title = av_strdup(s->filename);
00083     if (!sdl->icon_title)
00084         sdl->icon_title = av_strdup(sdl->window_title);
00085 
00086     if (SDL_WasInit(SDL_INIT_VIDEO)) {
00087         av_log(s, AV_LOG_ERROR,
00088                "SDL video subsystem was already inited, aborting.\n");
00089         sdl->sdl_was_already_inited = 1;
00090         ret = AVERROR(EINVAL);
00091         goto fail;
00092     }
00093 
00094     if (SDL_Init(SDL_INIT_VIDEO) != 0) {
00095         av_log(s, AV_LOG_ERROR, "Unable to initialize SDL: %s\n", SDL_GetError());
00096         ret = AVERROR(EINVAL);
00097         goto fail;
00098     }
00099 
00100     if (   s->nb_streams > 1
00101         || encctx->codec_type != AVMEDIA_TYPE_VIDEO
00102         || encctx->codec_id   != CODEC_ID_RAWVIDEO) {
00103         av_log(s, AV_LOG_ERROR, "Only supports one rawvideo stream\n");
00104         ret = AVERROR(EINVAL);
00105         goto fail;
00106     }
00107 
00108     for (i = 0; sdl_overlay_pix_fmt_map[i].pix_fmt != PIX_FMT_NONE; i++) {
00109         if (sdl_overlay_pix_fmt_map[i].pix_fmt == encctx->pix_fmt) {
00110             sdl->overlay_fmt = sdl_overlay_pix_fmt_map[i].overlay_fmt;
00111             break;
00112         }
00113     }
00114 
00115     if (!sdl->overlay_fmt) {
00116         av_log(s, AV_LOG_ERROR,
00117                "Unsupported pixel format '%s', choose one of yuv420p, yuyv422, or uyvy422.\n",
00118                av_get_pix_fmt_name(encctx->pix_fmt));
00119         ret = AVERROR(EINVAL);
00120         goto fail;
00121     }
00122 
00123     if (sdl->window_size) {
00124         if (av_parse_video_size(&sdl->window_width, &sdl->window_height,
00125                                 sdl->window_size) < 0) {
00126             av_log(s, AV_LOG_ERROR, "Invalid window size '%s'\n", sdl->window_size);
00127             ret = AVERROR(EINVAL);
00128             goto fail;
00129         }
00130     }
00131 
00132     /* compute overlay width and height from the codec context information */
00133     sar = st->sample_aspect_ratio.num ? av_q2d(st->sample_aspect_ratio) : 1;
00134     dar = sar * (float)encctx->width / (float)encctx->height;
00135 
00136     /* we suppose the screen has a 1/1 sample aspect ratio */
00137     sdl->overlay_height = encctx->height;
00138     sdl->overlay_width = ((int)rint(sdl->overlay_height * dar));
00139     if (sdl->overlay_width > encctx->width) {
00140         sdl->overlay_width = encctx->width;
00141         sdl->overlay_height = ((int)rint(sdl->overlay_width / dar));
00142     }
00143 
00144     if (!sdl->window_width || !sdl->window_height) {
00145         sdl->window_width  = sdl->overlay_width;
00146         sdl->window_height = sdl->overlay_height;
00147     }
00148 
00149     SDL_WM_SetCaption(sdl->window_title, sdl->icon_title);
00150     sdl->surface = SDL_SetVideoMode(sdl->window_width, sdl->window_height,
00151                                     24, SDL_SWSURFACE);
00152     if (!sdl->surface) {
00153         av_log(s, AV_LOG_ERROR, "Unable to set video mode: %s\n", SDL_GetError());
00154         ret = AVERROR(EINVAL);
00155         goto fail;
00156     }
00157 
00158     sdl->overlay = SDL_CreateYUVOverlay(sdl->overlay_width, sdl->overlay_height,
00159                                         sdl->overlay_fmt, sdl->surface);
00160     if (!sdl->overlay || sdl->overlay->pitches[0] < sdl->overlay_width) {
00161         av_log(s, AV_LOG_ERROR,
00162                "SDL does not support an overlay with size of %dx%d pixels.\n",
00163                sdl->overlay_width, sdl->overlay_height);
00164         ret = AVERROR(EINVAL);
00165         goto fail;
00166     }
00167 
00168     av_log(s, AV_LOG_INFO, "w:%d h:%d fmt:%s sar:%f -> w:%d h:%d\n",
00169            encctx->width, encctx->height, av_get_pix_fmt_name(encctx->pix_fmt), sar,
00170            sdl->window_width, sdl->window_height);
00171     return 0;
00172 
00173 fail:
00174     sdl_write_trailer(s);
00175     return ret;
00176 }
00177 
00178 static int sdl_write_packet(AVFormatContext *s, AVPacket *pkt)
00179 {
00180     SDLContext *sdl = s->priv_data;
00181     AVCodecContext *encctx = s->streams[0]->codec;
00182     SDL_Rect rect = { 0, 0, sdl->window_width, sdl->window_height };
00183     AVPicture pict;
00184     int i;
00185 
00186     avpicture_fill(&pict, pkt->data, encctx->pix_fmt, encctx->width, encctx->height);
00187 
00188     SDL_FillRect(sdl->surface, &sdl->surface->clip_rect,
00189                  SDL_MapRGB(sdl->surface->format, 0, 0, 0));
00190     SDL_LockYUVOverlay(sdl->overlay);
00191     for (i = 0; i < 3; i++) {
00192         sdl->overlay->pixels [i] = pict.data    [i];
00193         sdl->overlay->pitches[i] = pict.linesize[i];
00194     }
00195     SDL_DisplayYUVOverlay(sdl->overlay, &rect);
00196     SDL_UnlockYUVOverlay(sdl->overlay);
00197 
00198     SDL_UpdateRect(sdl->surface, 0, 0, sdl->overlay_width, sdl->overlay_height);
00199 
00200     return 0;
00201 }
00202 
00203 #define OFFSET(x) offsetof(SDLContext,x)
00204 
00205 static const AVOption options[] = {
00206     { "window_title", "SDL window title",           OFFSET(window_title),  FF_OPT_TYPE_STRING, {.str = NULL }, 0,  0, AV_OPT_FLAG_ENCODING_PARAM },
00207     { "icon_title",   "SDL iconified window title", OFFSET(icon_title)  ,  FF_OPT_TYPE_STRING, {.str = NULL }, 0,  0, AV_OPT_FLAG_ENCODING_PARAM },
00208     { "window_size",  "SDL window forced size",     OFFSET(window_size) ,  FF_OPT_TYPE_STRING, {.str = NULL }, 0,  0, AV_OPT_FLAG_ENCODING_PARAM },
00209     { NULL },
00210 };
00211 
00212 static const AVClass sdl_class = {
00213     .class_name = "sdl outdev",
00214     .item_name  = av_default_item_name,
00215     .option     = options,
00216     .version    = LIBAVUTIL_VERSION_INT,
00217 };
00218 
00219 AVOutputFormat ff_sdl_muxer = {
00220     .name           = "sdl",
00221     .long_name      = NULL_IF_CONFIG_SMALL("SDL output device"),
00222     .priv_data_size = sizeof(SDLContext),
00223     .audio_codec    = CODEC_ID_NONE,
00224     .video_codec    = CODEC_ID_RAWVIDEO,
00225     .write_header   = sdl_write_header,
00226     .write_packet   = sdl_write_packet,
00227     .write_trailer  = sdl_write_trailer,
00228     .flags          = AVFMT_NOFILE,
00229     .priv_class     = &sdl_class,
00230 };