FFmpeg
fbdev_enc.c
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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/file_open.h"
27 #include "libavutil/pixdesc.h"
28 #include "libavutil/log.h"
29 #include "libavutil/opt.h"
30 #include "libavformat/avformat.h"
31 #include "fbdev_common.h"
32 #include "avdevice.h"
33 
34 typedef struct {
35  AVClass *class; ///< class for private options
36  int xoffset; ///< x coordinate of top left corner
37  int yoffset; ///< y coordinate of top left corner
38  struct fb_var_screeninfo varinfo; ///< framebuffer variable info
39  struct fb_fix_screeninfo fixinfo; ///< framebuffer fixed info
40  int fd; ///< framebuffer device file descriptor
41  uint8_t *data; ///< framebuffer data
42 } FBDevContext;
43 
45 {
46  FBDevContext *fbdev = h->priv_data;
48  int ret, flags = O_RDWR;
49  const char* device;
50 
51  if (h->nb_streams != 1 || h->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO) {
52  av_log(fbdev, AV_LOG_ERROR, "Only a single video stream is supported.\n");
53  return AVERROR(EINVAL);
54  }
55 
56  if (h->url[0])
57  device = h->url;
58  else
59  device = ff_fbdev_default_device();
60 
61  if ((fbdev->fd = avpriv_open(device, flags)) == -1) {
62  ret = AVERROR(errno);
64  "Could not open framebuffer device '%s': %s\n",
65  device, av_err2str(ret));
66  return ret;
67  }
68 
69  if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
70  ret = AVERROR(errno);
71  av_log(h, AV_LOG_ERROR, "FBIOGET_VSCREENINFO: %s\n", av_err2str(ret));
72  goto fail;
73  }
74 
75  if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
76  ret = AVERROR(errno);
77  av_log(h, AV_LOG_ERROR, "FBIOGET_FSCREENINFO: %s\n", av_err2str(ret));
78  goto fail;
79  }
80 
82  if (pix_fmt == AV_PIX_FMT_NONE) {
83  ret = AVERROR(EINVAL);
84  av_log(h, AV_LOG_ERROR, "Framebuffer pixel format not supported.\n");
85  goto fail;
86  }
87 
88  fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_WRITE, MAP_SHARED, fbdev->fd, 0);
89  if (fbdev->data == MAP_FAILED) {
90  ret = AVERROR(errno);
91  av_log(h, AV_LOG_ERROR, "Error in mmap(): %s\n", av_err2str(ret));
92  goto fail;
93  }
94 
95  return 0;
96  fail:
97  close(fbdev->fd);
98  return ret;
99 }
100 
102 {
103  FBDevContext *fbdev = h->priv_data;
104  const uint8_t *pin;
105  uint8_t *pout;
106  enum AVPixelFormat fb_pix_fmt;
107  int disp_height;
108  int bytes_to_copy;
109  AVCodecParameters *par = h->streams[0]->codecpar;
110  enum AVPixelFormat video_pix_fmt = par->format;
111  int video_width = par->width;
112  int video_height = par->height;
113  int bytes_per_pixel = ((par->bits_per_coded_sample + 7) >> 3);
114  int src_line_size = video_width * bytes_per_pixel;
115  int i;
116 
117  if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
119  "Error refreshing variable info: %s\n", av_err2str(AVERROR(errno)));
120 
121  fb_pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
122 
123  if (fb_pix_fmt != video_pix_fmt) {
124  av_log(h, AV_LOG_ERROR, "Pixel format %s is not supported, use %s\n",
125  av_get_pix_fmt_name(video_pix_fmt), av_get_pix_fmt_name(fb_pix_fmt));
126  return AVERROR(EINVAL);
127  }
128 
129  disp_height = FFMIN(fbdev->varinfo.yres, video_height);
130  bytes_to_copy = FFMIN(fbdev->varinfo.xres, video_width) * bytes_per_pixel;
131 
132  pin = pkt->data;
133  pout = fbdev->data +
134  bytes_per_pixel * fbdev->varinfo.xoffset +
135  fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
136 
137  if (fbdev->xoffset) {
138  if (fbdev->xoffset < 0) {
139  if (-fbdev->xoffset >= video_width) //nothing to display
140  return 0;
141  bytes_to_copy += fbdev->xoffset * bytes_per_pixel;
142  pin -= fbdev->xoffset * bytes_per_pixel;
143  } else {
144  int diff = (video_width + fbdev->xoffset) - fbdev->varinfo.xres;
145  if (diff > 0) {
146  if (diff >= video_width) //nothing to display
147  return 0;
148  bytes_to_copy -= diff * bytes_per_pixel;
149  }
150  pout += bytes_per_pixel * fbdev->xoffset;
151  }
152  }
153 
154  if (fbdev->yoffset) {
155  if (fbdev->yoffset < 0) {
156  if (-fbdev->yoffset >= video_height) //nothing to display
157  return 0;
158  disp_height += fbdev->yoffset;
159  pin -= fbdev->yoffset * src_line_size;
160  } else {
161  int diff = (video_height + fbdev->yoffset) - fbdev->varinfo.yres;
162  if (diff > 0) {
163  if (diff >= video_height) //nothing to display
164  return 0;
165  disp_height -= diff;
166  }
167  pout += fbdev->yoffset * fbdev->fixinfo.line_length;
168  }
169  }
170 
171  for (i = 0; i < disp_height; i++) {
172  memcpy(pout, pin, bytes_to_copy);
173  pout += fbdev->fixinfo.line_length;
174  pin += src_line_size;
175  }
176 
177  return 0;
178 }
179 
181 {
182  FBDevContext *fbdev = h->priv_data;
183  munmap(fbdev->data, fbdev->fixinfo.smem_len);
184  close(fbdev->fd);
185  return 0;
186 }
187 
189 {
190  return ff_fbdev_get_device_list(device_list);
191 }
192 
193 #define OFFSET(x) offsetof(FBDevContext, x)
194 #define ENC AV_OPT_FLAG_ENCODING_PARAM
195 static const AVOption options[] = {
196  { "xoffset", "set x coordinate of top left corner", OFFSET(xoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
197  { "yoffset", "set y coordinate of top left corner", OFFSET(yoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
198  { NULL }
199 };
200 
201 static const AVClass fbdev_class = {
202  .class_name = "fbdev outdev",
203  .item_name = av_default_item_name,
204  .option = options,
205  .version = LIBAVUTIL_VERSION_INT,
207 };
208 
210  .name = "fbdev",
211  .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
212  .priv_data_size = sizeof(FBDevContext),
213  .audio_codec = AV_CODEC_ID_NONE,
214  .video_codec = AV_CODEC_ID_RAWVIDEO,
218  .get_device_list = fbdev_get_device_list,
220  .priv_class = &fbdev_class,
221 };
ff_fbdev_default_device
const char * ff_fbdev_default_device()
Definition: fbdev_common.c:65
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVOutputFormat::name
const char * name
Definition: avformat.h:510
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:54
AVFMT_VARIABLE_FPS
#define AVFMT_VARIABLE_FPS
Format allows variable fps.
Definition: avformat.h:484
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:481
ENC
#define ENC
Definition: fbdev_enc.c:194
AV_CODEC_ID_RAWVIDEO
@ AV_CODEC_ID_RAWVIDEO
Definition: codec_id.h:65
pixdesc.h
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVOption
AVOption.
Definition: opt.h:251
data
const char data[16]
Definition: mxf.c:146
FBDevContext::xoffset
int xoffset
x coordinate of top left corner
Definition: fbdev_enc.c:36
fail
#define fail()
Definition: checkasm.h:134
FBDevContext::fixinfo
struct fb_fix_screeninfo fixinfo
fixed info;
Definition: fbdev_dec.c:60
ff_get_pixfmt_from_fb_varinfo
enum AVPixelFormat ff_get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
Definition: fbdev_common.c:49
pkt
AVPacket * pkt
Definition: movenc.c:59
FBDevContext::yoffset
int yoffset
y coordinate of top left corner
Definition: fbdev_enc.c:37
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
fbdev_write_packet
static int fbdev_write_packet(AVFormatContext *h, AVPacket *pkt)
Definition: fbdev_enc.c:101
ff_fbdev_get_device_list
int ff_fbdev_get_device_list(AVDeviceInfoList *device_list)
Definition: fbdev_common.c:73
s
#define s(width, name)
Definition: cbs_vp9.c:256
avpriv_open
int avpriv_open(const char *filename, int flags,...)
A wrapper for open() setting O_CLOEXEC.
Definition: file_open.c:67
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demuxing_decoding.c:41
FBDevContext::fd
int fd
framebuffer device file descriptor
Definition: fbdev_dec.c:54
fbdev_write_trailer
static av_cold int fbdev_write_trailer(AVFormatContext *h)
Definition: fbdev_enc.c:180
file_open.h
fbdev_get_device_list
static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list)
Definition: fbdev_enc.c:188
if
if(ret)
Definition: filter_design.txt:179
AVFormatContext
Format I/O context.
Definition: avformat.h:1216
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
write_trailer
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:100
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT
@ AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT
Definition: log.h:40
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:115
av_err2str
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:121
AVFMT_NOFILE
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:470
OFFSET
#define OFFSET(x)
Definition: fbdev_enc.c:193
avdevice.h
fbdev_common.h
ff_fbdev_muxer
const AVOutputFormat ff_fbdev_muxer
Definition: fbdev_enc.c:209
log.h
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
AVOutputFormat
Definition: avformat.h:509
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
fbdev_write_header
static av_cold int fbdev_write_header(AVFormatContext *h)
Definition: fbdev_enc.c:44
AVCodecParameters::height
int height
Definition: codec_par.h:129
FBDevContext
Definition: fbdev_dec.c:48
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
write_packet
static int write_packet(Muxer *mux, OutputStream *ost, AVPacket *pkt)
Definition: ffmpeg_mux.c:61
ret
ret
Definition: filter_design.txt:187
AVClass::class_name
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:71
AVDeviceInfoList
List of devices.
Definition: avdevice.h:473
avformat.h
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:225
FBDevContext::varinfo
struct fb_var_screeninfo varinfo
variable info;
Definition: fbdev_dec.c:59
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:104
AVCodecParameters::format
int format
Definition: codec_par.h:86
options
static const AVOption options[]
Definition: fbdev_enc.c:195
diff
static av_always_inline int diff(const uint32_t a, const uint32_t b)
Definition: vf_palettegen.c:139
AVPacket
This structure stores compressed data.
Definition: packet.h:351
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
h
h
Definition: vp9dsp_template.c:2038
write_header
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:346
FBDevContext::data
uint8_t * data
framebuffer data
Definition: fbdev_dec.c:62
fbdev_class
static const AVClass fbdev_class
Definition: fbdev_enc.c:201
av_get_pix_fmt_name
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:2778