fbdev.c
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1 /*
2  * Copyright (c) 2011 Stefano Sabatini
3  * Copyright (c) 2009 Giliard B. de Freitas <giliarde@gmail.com>
4  * Copyright (C) 2002 Gunnar Monell <gmo@linux.nu>
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
30 /* #define DEBUG */
31 
32 #include <unistd.h>
33 #include <fcntl.h>
34 #include <sys/ioctl.h>
35 #include <sys/mman.h>
36 #include <time.h>
37 #include <linux/fb.h>
38 
39 #include "libavutil/log.h"
40 #include "libavutil/mem.h"
41 #include "libavutil/opt.h"
42 #include "libavutil/time.h"
43 #include "libavutil/parseutils.h"
44 #include "libavutil/pixdesc.h"
45 #include "libavformat/avformat.h"
46 #include "libavformat/internal.h"
47 
52 };
53 
55  // bpp, red_offset, green_offset, blue_offset, alpha_offset, pixfmt
56  { 32, 0, 8, 16, 24, AV_PIX_FMT_RGBA },
57  { 32, 16, 8, 0, 24, AV_PIX_FMT_BGRA },
58  { 32, 8, 16, 24, 0, AV_PIX_FMT_ARGB },
59  { 32, 3, 2, 8, 0, AV_PIX_FMT_ABGR },
60  { 24, 0, 8, 16, 0, AV_PIX_FMT_RGB24 },
61  { 24, 16, 8, 0, 0, AV_PIX_FMT_BGR24 },
62 };
63 
64 static enum AVPixelFormat get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
65 {
66  int i;
67 
68  for (i = 0; i < FF_ARRAY_ELEMS(rgb_pixfmt_map); i++) {
69  struct rgb_pixfmt_map_entry *entry = &rgb_pixfmt_map[i];
70  if (entry->bits_per_pixel == varinfo->bits_per_pixel &&
71  entry->red_offset == varinfo->red.offset &&
72  entry->green_offset == varinfo->green.offset &&
73  entry->blue_offset == varinfo->blue.offset)
74  return entry->pixfmt;
75  }
76 
77  return AV_PIX_FMT_NONE;
78 }
79 
80 typedef struct {
81  AVClass *class;
82  int frame_size;
84  char *framerate;
85  int64_t time_frame;
86 
87  int fd;
88  int width, height;
91 
92  struct fb_var_screeninfo varinfo;
93  struct fb_fix_screeninfo fixinfo;
94 
96 } FBDevContext;
97 
99 {
100  FBDevContext *fbdev = avctx->priv_data;
101  AVStream *st = NULL;
102  enum AVPixelFormat pix_fmt;
103  int ret, flags = O_RDONLY;
104 
105  ret = av_parse_video_rate(&fbdev->framerate_q, fbdev->framerate);
106  if (ret < 0) {
107  av_log(avctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n", fbdev->framerate);
108  return ret;
109  }
110 
111  if (!(st = avformat_new_stream(avctx, NULL)))
112  return AVERROR(ENOMEM);
113  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
114 
115  /* NONBLOCK is ignored by the fbdev driver, only set for consistency */
116  if (avctx->flags & AVFMT_FLAG_NONBLOCK)
117  flags |= O_NONBLOCK;
118 
119  if ((fbdev->fd = open(avctx->filename, flags)) == -1) {
120  ret = AVERROR(errno);
121  av_log(avctx, AV_LOG_ERROR,
122  "Could not open framebuffer device '%s': %s\n",
123  avctx->filename, strerror(ret));
124  return ret;
125  }
126 
127  if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
128  ret = AVERROR(errno);
129  av_log(avctx, AV_LOG_ERROR,
130  "FBIOGET_VSCREENINFO: %s\n", strerror(errno));
131  goto fail;
132  }
133 
134  if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
135  ret = AVERROR(errno);
136  av_log(avctx, AV_LOG_ERROR,
137  "FBIOGET_FSCREENINFO: %s\n", strerror(errno));
138  goto fail;
139  }
140 
141  pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
142  if (pix_fmt == AV_PIX_FMT_NONE) {
143  ret = AVERROR(EINVAL);
144  av_log(avctx, AV_LOG_ERROR,
145  "Framebuffer pixel format not supported.\n");
146  goto fail;
147  }
148 
149  fbdev->width = fbdev->varinfo.xres;
150  fbdev->height = fbdev->varinfo.yres;
151  fbdev->bytes_per_pixel = (fbdev->varinfo.bits_per_pixel + 7) >> 3;
152  fbdev->frame_linesize = fbdev->width * fbdev->bytes_per_pixel;
153  fbdev->frame_size = fbdev->frame_linesize * fbdev->height;
154  fbdev->time_frame = AV_NOPTS_VALUE;
155  fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_READ, MAP_SHARED, fbdev->fd, 0);
156  if (fbdev->data == MAP_FAILED) {
157  ret = AVERROR(errno);
158  av_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", strerror(errno));
159  goto fail;
160  }
161 
164  st->codec->width = fbdev->width;
165  st->codec->height = fbdev->height;
166  st->codec->pix_fmt = pix_fmt;
167  st->codec->time_base = (AVRational){fbdev->framerate_q.den, fbdev->framerate_q.num};
168  st->codec->bit_rate =
169  fbdev->width * fbdev->height * fbdev->bytes_per_pixel * av_q2d(fbdev->framerate_q) * 8;
170 
171  av_log(avctx, AV_LOG_INFO,
172  "w:%d h:%d bpp:%d pixfmt:%s fps:%d/%d bit_rate:%d\n",
173  fbdev->width, fbdev->height, fbdev->varinfo.bits_per_pixel,
174  av_get_pix_fmt_name(pix_fmt),
175  fbdev->framerate_q.num, fbdev->framerate_q.den,
176  st->codec->bit_rate);
177  return 0;
178 
179 fail:
180  close(fbdev->fd);
181  return ret;
182 }
183 
185 {
186  FBDevContext *fbdev = avctx->priv_data;
187  int64_t curtime, delay;
188  struct timespec ts;
189  int i, ret;
190  uint8_t *pin, *pout;
191 
192  if (fbdev->time_frame == AV_NOPTS_VALUE)
193  fbdev->time_frame = av_gettime();
194 
195  /* wait based on the frame rate */
196  curtime = av_gettime();
197  delay = fbdev->time_frame - curtime;
198  av_dlog(avctx,
199  "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
200  fbdev->time_frame, curtime, delay);
201  if (delay > 0) {
202  if (avctx->flags & AVFMT_FLAG_NONBLOCK)
203  return AVERROR(EAGAIN);
204  ts.tv_sec = delay / 1000000;
205  ts.tv_nsec = (delay % 1000000) * 1000;
206  while (nanosleep(&ts, &ts) < 0 && errno == EINTR);
207  }
208  /* compute the time of the next frame */
209  fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->framerate_q);
210 
211  if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0)
212  return ret;
213 
214  /* refresh fbdev->varinfo, visible data position may change at each call */
215  if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
216  av_log(avctx, AV_LOG_WARNING,
217  "Error refreshing variable info: %s\n", strerror(errno));
218 
219  pkt->pts = curtime;
220 
221  /* compute visible data offset */
222  pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset +
223  fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
224  pout = pkt->data;
225 
226  // TODO it'd be nice if the lines were aligned
227  for (i = 0; i < fbdev->height; i++) {
228  memcpy(pout, pin, fbdev->frame_linesize);
229  pin += fbdev->fixinfo.line_length;
230  pout += fbdev->frame_linesize;
231  }
232 
233  return fbdev->frame_size;
234 }
235 
237 {
238  FBDevContext *fbdev = avctx->priv_data;
239 
240  munmap(fbdev->data, fbdev->frame_size);
241  close(fbdev->fd);
242 
243  return 0;
244 }
245 
246 #define OFFSET(x) offsetof(FBDevContext, x)
247 #define DEC AV_OPT_FLAG_DECODING_PARAM
248 static const AVOption options[] = {
249  { "framerate","", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0, DEC },
250  { NULL },
251 };
252 
253 static const AVClass fbdev_class = {
254  .class_name = "fbdev indev",
255  .item_name = av_default_item_name,
256  .option = options,
257  .version = LIBAVUTIL_VERSION_INT,
258 };
259 
261  .name = "fbdev",
262  .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
263  .priv_data_size = sizeof(FBDevContext),
267  .flags = AVFMT_NOFILE,
268  .priv_class = &fbdev_class,
269 };
#define DEC
Definition: fbdev.c:247
int height
assumed frame resolution
Definition: fbdev.c:88
int av_parse_video_rate(AVRational *rate, const char *arg)
Parse str and store the detected values in *rate.
Definition: parseutils.c:122
AVOption.
Definition: opt.h:233
int blue_offset
Definition: fbdev.c:50
char * framerate
framerate string set by a private option
Definition: fbdev.c:84
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:67
memory handling functions
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:3283
int alpha_offset
Definition: fbdev.c:50
int num
numerator
Definition: rational.h:44
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1533
AVInputFormat ff_fbdev_demuxer
Definition: fbdev.c:260
av_dlog(ac->avr,"%d samples - audio_convert: %s to %s (%s)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic?ac->func_descr_generic:ac->func_descr)
int frame_linesize
linesize of the output frame, it is assumed to be constant
Definition: fbdev.c:89
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1465
int frame_size
size in bytes of a grabbed frame
Definition: fbdev.c:82
Format I/O context.
Definition: avformat.h:828
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:38
uint8_t
AVOptions.
struct fb_var_screeninfo varinfo
variable info;
Definition: fbdev.c:92
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:95
int64_t time_frame
time for the next frame to output (in 1/1000000 units)
Definition: fbdev.c:85
static double av_q2d(AVRational a)
Convert rational to double.
Definition: rational.h:69
uint8_t * data
Definition: avcodec.h:915
static int flags
Definition: log.c:42
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
Definition: fbdev.c:48
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:56
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:96
enum AVPixelFormat pixfmt
Definition: fbdev.c:51
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
AVStream * avformat_new_stream(AVFormatContext *s, AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2736
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:93
int green_offset
Definition: fbdev.c:50
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:94
struct fb_fix_screeninfo fixinfo
fixed info;
Definition: fbdev.c:93
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:641
struct AVRational AVRational
rational number numerator/denominator
int bit_rate
the average bitrate
Definition: avcodec.h:1404
char filename[1024]
input or output filename
Definition: avformat.h:878
int width
picture width / height.
Definition: avcodec.h:1508
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:68
enum AVPixelFormat pix_fmt
Definition: movenc.c:801
AVRational framerate_q
framerate
Definition: fbdev.c:83
LIBAVUTIL_VERSION_INT
Definition: eval.c:52
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:536
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:37
Stream structure.
Definition: avformat.h:622
NULL
Definition: eval.c:52
enum AVMediaType codec_type
Definition: avcodec.h:1347
static av_cold int fbdev_read_header(AVFormatContext *avctx)
Definition: fbdev.c:98
enum AVCodecID codec_id
Definition: avcodec.h:1350
static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt)
Definition: fbdev.c:184
av_default_item_name
Definition: dnxhdenc.c:43
int width
Definition: fbdev.c:88
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:326
int bytes_per_pixel
Definition: fbdev.c:90
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
static av_cold int fbdev_read_close(AVFormatContext *avctx)
Definition: fbdev.c:236
Describe the class of an AVClass context structure.
Definition: log.h:33
rational number numerator/denominator
Definition: rational.h:43
misc parsing utilities
int height
Definition: gxfenc.c:72
Main libavformat public API header.
uint8_t * data
framebuffer data
Definition: fbdev.c:95
static enum AVPixelFormat get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
Definition: fbdev.c:64
int den
denominator
Definition: rational.h:45
int red_offset
Definition: fbdev.c:50
static struct rgb_pixfmt_map_entry rgb_pixfmt_map[]
Definition: fbdev.c:54
void * priv_data
Format private data.
Definition: avformat.h:848
static const AVClass fbdev_class
Definition: fbdev.c:253
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:455
static const AVOption options[]
Definition: fbdev.c:248
#define OFFSET(x)
Definition: fbdev.c:246
const char * av_get_pix_fmt_name(enum AVPixelFormat pix_fmt)
Return the short name for a pixel format, NULL in case pix_fmt is unknown.
Definition: pixdesc.c:1377
AVPixelFormat
Pixel format.
Definition: pixfmt.h:63
This structure stores compressed data.
Definition: avcodec.h:898
int fd
framebuffer device file descriptor
Definition: fbdev.c:87
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:908
int bits_per_pixel
Definition: fbdev.c:49