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/pixdesc.h"
27 #include "libavutil/log.h"
28 #include "libavutil/mem.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 
81  pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
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  uint8_t *pin, *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)
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 
180 {
181  FBDevContext *fbdev = h->priv_data;
182  munmap(fbdev->data, fbdev->fixinfo.smem_len);
183  close(fbdev->fd);
184  return 0;
185 }
186 
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,
206 };
207 
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,
217  .get_device_list = fbdev_get_device_list,
219  .priv_class = &fbdev_class,
220 };
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:690
#define NULL
Definition: coverity.c:32
static enum AVPixelFormat pix_fmt
AVOption.
Definition: opt.h:246
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
Memory handling functions.
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
static AVPacket pkt
const char * ff_fbdev_default_device()
Definition: fbdev_common.c:64
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3960
Format I/O context.
Definition: avformat.h:1358
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:72
uint8_t
#define av_cold
Definition: attributes.h:82
int width
Video only.
Definition: avcodec.h:4034
AVOptions.
struct fb_var_screeninfo varinfo
variable info;
Definition: fbdev_dec.c:59
#define OFFSET(x)
Definition: fbdev_enc.c:192
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
int avpriv_open(const char *filename, int flags,...)
A wrapper for open() setting O_CLOEXEC.
Definition: file_open.c:66
uint8_t * data
Definition: avcodec.h:1480
AVOutputFormat ff_fbdev_muxer
Definition: fbdev_enc.c:208
#define av_log(a,...)
Main libavdevice API header.
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
char * url
input or output URL.
Definition: avformat.h:1454
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
#define fail()
Definition: checkasm.h:122
static const AVOption options[]
Definition: fbdev_enc.c:194
struct fb_fix_screeninfo fixinfo
fixed info;
Definition: fbdev_dec.c:60
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
#define FFMIN(a, b)
Definition: common.h:96
int yoffset
y coordinate of top left corner
Definition: fbdev_enc.c:37
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:94
static av_cold int fbdev_write_header(AVFormatContext *h)
Definition: fbdev_enc.c:44
const char * name
Definition: avformat.h:505
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:119
#define s(width, name)
Definition: cbs_vp9.c:257
int xoffset
x coordinate of top left corner
Definition: fbdev_enc.c:36
if(ret)
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
static av_cold int fbdev_write_trailer(AVFormatContext *h)
Definition: fbdev_enc.c:179
#define ENC
Definition: fbdev_enc.c:193
int ff_fbdev_get_device_list(AVDeviceInfoList *device_list)
Definition: fbdev_common.c:72
Describe the class of an AVClass context structure.
Definition: log.h:67
static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list)
Definition: fbdev_enc.c:187
static int fbdev_write_packet(AVFormatContext *h, AVPacket *pkt)
Definition: fbdev_enc.c:101
List of devices.
Definition: avdevice.h:460
#define flags(name, subs,...)
Definition: cbs_av1.c:561
Main libavformat public API header.
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:463
enum AVPixelFormat ff_get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
Definition: fbdev_common.c:48
#define AVFMT_VARIABLE_FPS
Format allows variable fps.
Definition: avformat.h:470
static av_always_inline int diff(const uint32_t a, const uint32_t b)
void * priv_data
Format private data.
Definition: avformat.h:1386
static const AVClass fbdev_class
Definition: fbdev_enc.c:200
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:349
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:4010
uint8_t * data
framebuffer data
Definition: fbdev_dec.c:62
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
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:2438
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
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1457
int fd
framebuffer device file descriptor
Definition: fbdev_dec.c:54