1 /*
2 * Copyright (c) 2013 Lukasz Marek
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 <unistd.h>
22 #include <fcntl.h>
23 #include <sys/ioctl.h>
24 #include <sys/mman.h>
25 #include <linux/fb.h>
26 #include "libavutil/pixdesc.h"
27 #include "libavutil/log.h"
28 #include "libavutil/opt.h"
29 #include "libavformat/avformat.h"
30 #include "fbdev_common.h"
31 #include "avdevice.h"
32
33 typedef struct {
34 AVClass *class; ///< class for private options
35 int xoffset; ///< x coordinate of top left corner
36 int yoffset; ///< y coordinate of top left corner
37 struct fb_var_screeninfo varinfo; ///< framebuffer variable info
38 struct fb_fix_screeninfo fixinfo; ///< framebuffer fixed info
39 int fd; ///< framebuffer device file descriptor
40 uint8_t *data; ///< framebuffer data
41 } FBDevContext;
42
fbdev_write_header(AVFormatContext * h)43 static av_cold int fbdev_write_header(AVFormatContext *h)
44 {
45 FBDevContext *fbdev = h->priv_data;
46 enum AVPixelFormat pix_fmt;
47 int ret, flags = O_RDWR;
48 const char* device;
49
50 if (h->nb_streams != 1 || h->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO) {
51 av_log(fbdev, AV_LOG_ERROR, "Only a single video stream is supported.\n");
52 return AVERROR(EINVAL);
53 }
54
55 if (h->url[0])
56 device = h->url;
57 else
58 device = ff_fbdev_default_device();
59
60 if ((fbdev->fd = avpriv_open(device, flags)) == -1) {
61 ret = AVERROR(errno);
62 av_log(h, AV_LOG_ERROR,
63 "Could not open framebuffer device '%s': %s\n",
64 device, av_err2str(ret));
65 return ret;
66 }
67
68 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
69 ret = AVERROR(errno);
70 av_log(h, AV_LOG_ERROR, "FBIOGET_VSCREENINFO: %s\n", av_err2str(ret));
71 goto fail;
72 }
73
74 if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
75 ret = AVERROR(errno);
76 av_log(h, AV_LOG_ERROR, "FBIOGET_FSCREENINFO: %s\n", av_err2str(ret));
77 goto fail;
78 }
79
80 pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
81 if (pix_fmt == AV_PIX_FMT_NONE) {
82 ret = AVERROR(EINVAL);
83 av_log(h, AV_LOG_ERROR, "Framebuffer pixel format not supported.\n");
84 goto fail;
85 }
86
87 fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_WRITE, MAP_SHARED, fbdev->fd, 0);
88 if (fbdev->data == MAP_FAILED) {
89 ret = AVERROR(errno);
90 av_log(h, AV_LOG_ERROR, "Error in mmap(): %s\n", av_err2str(ret));
91 goto fail;
92 }
93
94 return 0;
95 fail:
96 close(fbdev->fd);
97 return ret;
98 }
99
fbdev_write_packet(AVFormatContext * h,AVPacket * pkt)100 static int fbdev_write_packet(AVFormatContext *h, AVPacket *pkt)
101 {
102 FBDevContext *fbdev = h->priv_data;
103 const uint8_t *pin;
104 uint8_t *pout;
105 enum AVPixelFormat fb_pix_fmt;
106 int disp_height;
107 int bytes_to_copy;
108 AVCodecParameters *par = h->streams[0]->codecpar;
109 enum AVPixelFormat video_pix_fmt = par->format;
110 int video_width = par->width;
111 int video_height = par->height;
112 int bytes_per_pixel = ((par->bits_per_coded_sample + 7) >> 3);
113 int src_line_size = video_width * bytes_per_pixel;
114 int i;
115
116 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
117 av_log(h, AV_LOG_WARNING,
118 "Error refreshing variable info: %s\n", av_err2str(AVERROR(errno)));
119
120 fb_pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
121
122 if (fb_pix_fmt != video_pix_fmt) {
123 av_log(h, AV_LOG_ERROR, "Pixel format %s is not supported, use %s\n",
124 av_get_pix_fmt_name(video_pix_fmt), av_get_pix_fmt_name(fb_pix_fmt));
125 return AVERROR(EINVAL);
126 }
127
128 disp_height = FFMIN(fbdev->varinfo.yres, video_height);
129 bytes_to_copy = FFMIN(fbdev->varinfo.xres, video_width) * bytes_per_pixel;
130
131 pin = pkt->data;
132 pout = fbdev->data +
133 bytes_per_pixel * fbdev->varinfo.xoffset +
134 fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
135
136 if (fbdev->xoffset) {
137 if (fbdev->xoffset < 0) {
138 if (-fbdev->xoffset >= video_width) //nothing to display
139 return 0;
140 bytes_to_copy += fbdev->xoffset * bytes_per_pixel;
141 pin -= fbdev->xoffset * bytes_per_pixel;
142 } else {
143 int diff = (video_width + fbdev->xoffset) - fbdev->varinfo.xres;
144 if (diff > 0) {
145 if (diff >= video_width) //nothing to display
146 return 0;
147 bytes_to_copy -= diff * bytes_per_pixel;
148 }
149 pout += bytes_per_pixel * fbdev->xoffset;
150 }
151 }
152
153 if (fbdev->yoffset) {
154 if (fbdev->yoffset < 0) {
155 if (-fbdev->yoffset >= video_height) //nothing to display
156 return 0;
157 disp_height += fbdev->yoffset;
158 pin -= fbdev->yoffset * src_line_size;
159 } else {
160 int diff = (video_height + fbdev->yoffset) - fbdev->varinfo.yres;
161 if (diff > 0) {
162 if (diff >= video_height) //nothing to display
163 return 0;
164 disp_height -= diff;
165 }
166 pout += fbdev->yoffset * fbdev->fixinfo.line_length;
167 }
168 }
169
170 for (i = 0; i < disp_height; i++) {
171 memcpy(pout, pin, bytes_to_copy);
172 pout += fbdev->fixinfo.line_length;
173 pin += src_line_size;
174 }
175
176 return 0;
177 }
178
fbdev_write_trailer(AVFormatContext * h)179 static av_cold int fbdev_write_trailer(AVFormatContext *h)
180 {
181 FBDevContext *fbdev = h->priv_data;
182 munmap(fbdev->data, fbdev->fixinfo.smem_len);
183 close(fbdev->fd);
184 return 0;
185 }
186
fbdev_get_device_list(AVFormatContext * s,AVDeviceInfoList * device_list)187 static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list)
188 {
189 return ff_fbdev_get_device_list(device_list);
190 }
191
192 #define OFFSET(x) offsetof(FBDevContext, x)
193 #define ENC AV_OPT_FLAG_ENCODING_PARAM
194 static const AVOption options[] = {
195 { "xoffset", "set x coordinate of top left corner", OFFSET(xoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
196 { "yoffset", "set y coordinate of top left corner", OFFSET(yoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
197 { NULL }
198 };
199
200 static const AVClass fbdev_class = {
201 .class_name = "fbdev outdev",
202 .item_name = av_default_item_name,
203 .option = options,
204 .version = LIBAVUTIL_VERSION_INT,
205 .category = AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT,
206 };
207
208 const AVOutputFormat ff_fbdev_muxer = {
209 .name = "fbdev",
210 .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
211 .priv_data_size = sizeof(FBDevContext),
212 .audio_codec = AV_CODEC_ID_NONE,
213 .video_codec = AV_CODEC_ID_RAWVIDEO,
214 .write_header = fbdev_write_header,
215 .write_packet = fbdev_write_packet,
216 .write_trailer = fbdev_write_trailer,
217 .get_device_list = fbdev_get_device_list,
218 .flags = AVFMT_NOFILE | AVFMT_VARIABLE_FPS | AVFMT_NOTIMESTAMPS,
219 .priv_class = &fbdev_class,
220 };
221