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FFmpeg/libavdevice/fbdev_enc.c
Andreas Rheinhardt d5a0eba8a2 av(format|device): Add const to muxer packet data pointers
The packets given to muxers need not be writable,
so it is best to access them via const uint8_t*.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-07-09 19:37:53 +02:00

221 lines
7.4 KiB
C

/*
* Copyright (c) 2013 Lukasz Marek
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <linux/fb.h>
#include "libavutil/pixdesc.h"
#include "libavutil/log.h"
#include "libavutil/opt.h"
#include "libavformat/avformat.h"
#include "fbdev_common.h"
#include "avdevice.h"
typedef struct {
AVClass *class; ///< class for private options
int xoffset; ///< x coordinate of top left corner
int yoffset; ///< y coordinate of top left corner
struct fb_var_screeninfo varinfo; ///< framebuffer variable info
struct fb_fix_screeninfo fixinfo; ///< framebuffer fixed info
int fd; ///< framebuffer device file descriptor
uint8_t *data; ///< framebuffer data
} FBDevContext;
static av_cold int fbdev_write_header(AVFormatContext *h)
{
FBDevContext *fbdev = h->priv_data;
enum AVPixelFormat pix_fmt;
int ret, flags = O_RDWR;
const char* device;
if (h->nb_streams != 1 || h->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO) {
av_log(fbdev, AV_LOG_ERROR, "Only a single video stream is supported.\n");
return AVERROR(EINVAL);
}
if (h->url[0])
device = h->url;
else
device = ff_fbdev_default_device();
if ((fbdev->fd = avpriv_open(device, flags)) == -1) {
ret = AVERROR(errno);
av_log(h, AV_LOG_ERROR,
"Could not open framebuffer device '%s': %s\n",
device, av_err2str(ret));
return ret;
}
if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
ret = AVERROR(errno);
av_log(h, AV_LOG_ERROR, "FBIOGET_VSCREENINFO: %s\n", av_err2str(ret));
goto fail;
}
if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
ret = AVERROR(errno);
av_log(h, AV_LOG_ERROR, "FBIOGET_FSCREENINFO: %s\n", av_err2str(ret));
goto fail;
}
pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
if (pix_fmt == AV_PIX_FMT_NONE) {
ret = AVERROR(EINVAL);
av_log(h, AV_LOG_ERROR, "Framebuffer pixel format not supported.\n");
goto fail;
}
fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_WRITE, MAP_SHARED, fbdev->fd, 0);
if (fbdev->data == MAP_FAILED) {
ret = AVERROR(errno);
av_log(h, AV_LOG_ERROR, "Error in mmap(): %s\n", av_err2str(ret));
goto fail;
}
return 0;
fail:
close(fbdev->fd);
return ret;
}
static int fbdev_write_packet(AVFormatContext *h, AVPacket *pkt)
{
FBDevContext *fbdev = h->priv_data;
const uint8_t *pin;
uint8_t *pout;
enum AVPixelFormat fb_pix_fmt;
int disp_height;
int bytes_to_copy;
AVCodecParameters *par = h->streams[0]->codecpar;
enum AVPixelFormat video_pix_fmt = par->format;
int video_width = par->width;
int video_height = par->height;
int bytes_per_pixel = ((par->bits_per_coded_sample + 7) >> 3);
int src_line_size = video_width * bytes_per_pixel;
int i;
if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
av_log(h, AV_LOG_WARNING,
"Error refreshing variable info: %s\n", av_err2str(AVERROR(errno)));
fb_pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
if (fb_pix_fmt != video_pix_fmt) {
av_log(h, AV_LOG_ERROR, "Pixel format %s is not supported, use %s\n",
av_get_pix_fmt_name(video_pix_fmt), av_get_pix_fmt_name(fb_pix_fmt));
return AVERROR(EINVAL);
}
disp_height = FFMIN(fbdev->varinfo.yres, video_height);
bytes_to_copy = FFMIN(fbdev->varinfo.xres, video_width) * bytes_per_pixel;
pin = pkt->data;
pout = fbdev->data +
bytes_per_pixel * fbdev->varinfo.xoffset +
fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
if (fbdev->xoffset) {
if (fbdev->xoffset < 0) {
if (-fbdev->xoffset >= video_width) //nothing to display
return 0;
bytes_to_copy += fbdev->xoffset * bytes_per_pixel;
pin -= fbdev->xoffset * bytes_per_pixel;
} else {
int diff = (video_width + fbdev->xoffset) - fbdev->varinfo.xres;
if (diff > 0) {
if (diff >= video_width) //nothing to display
return 0;
bytes_to_copy -= diff * bytes_per_pixel;
}
pout += bytes_per_pixel * fbdev->xoffset;
}
}
if (fbdev->yoffset) {
if (fbdev->yoffset < 0) {
if (-fbdev->yoffset >= video_height) //nothing to display
return 0;
disp_height += fbdev->yoffset;
pin -= fbdev->yoffset * src_line_size;
} else {
int diff = (video_height + fbdev->yoffset) - fbdev->varinfo.yres;
if (diff > 0) {
if (diff >= video_height) //nothing to display
return 0;
disp_height -= diff;
}
pout += fbdev->yoffset * fbdev->fixinfo.line_length;
}
}
for (i = 0; i < disp_height; i++) {
memcpy(pout, pin, bytes_to_copy);
pout += fbdev->fixinfo.line_length;
pin += src_line_size;
}
return 0;
}
static av_cold int fbdev_write_trailer(AVFormatContext *h)
{
FBDevContext *fbdev = h->priv_data;
munmap(fbdev->data, fbdev->fixinfo.smem_len);
close(fbdev->fd);
return 0;
}
static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list)
{
return ff_fbdev_get_device_list(device_list);
}
#define OFFSET(x) offsetof(FBDevContext, x)
#define ENC AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "xoffset", "set x coordinate of top left corner", OFFSET(xoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
{ "yoffset", "set y coordinate of top left corner", OFFSET(yoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
{ NULL }
};
static const AVClass fbdev_class = {
.class_name = "fbdev outdev",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
.category = AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT,
};
const AVOutputFormat ff_fbdev_muxer = {
.name = "fbdev",
.long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
.priv_data_size = sizeof(FBDevContext),
.audio_codec = AV_CODEC_ID_NONE,
.video_codec = AV_CODEC_ID_RAWVIDEO,
.write_header = fbdev_write_header,
.write_packet = fbdev_write_packet,
.write_trailer = fbdev_write_trailer,
.get_device_list = fbdev_get_device_list,
.flags = AVFMT_NOFILE | AVFMT_VARIABLE_FPS | AVFMT_NOTIMESTAMPS,
.priv_class = &fbdev_class,
};