[FFmpeg-cvslog] Remove the legacy X11 screen grabber

Diego Biurrun git at videolan.org
Wed Mar 15 23:14:42 EET 2017


ffmpeg | branch: master | Diego Biurrun <diego at biurrun.de> | Wed Jul 27 11:25:19 2016 +0200| [4fef648d10bf3bcfd4b8fa5755c1128966a2427c] | committer: Diego Biurrun

Remove the legacy X11 screen grabber

The XCB screen grabber is a drop-in replacement and not under GPL.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=4fef648d10bf3bcfd4b8fa5755c1128966a2427c
---

 Changelog                |   1 +
 LICENSE                  |   1 -
 configure                |  13 +-
 libavdevice/Makefile     |   1 -
 libavdevice/alldevices.c |   1 -
 libavdevice/avdevice.h   |   2 +-
 libavdevice/x11grab.c    | 647 -----------------------------------------------
 7 files changed, 4 insertions(+), 662 deletions(-)

diff --git a/Changelog b/Changelog
index d3201b3..0d04f47 100644
--- a/Changelog
+++ b/Changelog
@@ -61,6 +61,7 @@ version <next>:
 - Duck TrueMotion 2.0 Real Time decoder
 - Intel QSV video scaling and deinterlacing filter
 - OpenH264 decoder wrapper
+- Removed the legacy X11 screen grabber, use XCB instead
 
 
 version 11:
diff --git a/LICENSE b/LICENSE
index 1eae4e7..a2de35c 100644
--- a/LICENSE
+++ b/LICENSE
@@ -13,7 +13,6 @@ configure to activate them. In this case, Libav's license changes to GPL v2+.
 
 Specifically, the GPL parts of Libav are
 
-- the X11 grabber in libavdevice/x11grab.c
 - the texi2pod.pl tool
 - the following filters in libavfilter:
     - vf_blackframe.c
diff --git a/configure b/configure
index e366dad..45f5256 100755
--- a/configure
+++ b/configure
@@ -227,7 +227,6 @@ External library support:
   --enable-libxcb-xfixes     X11 mouse rendering [auto]
   --enable-libxvid           MPEG-4 ASP video encoding
   --enable-openssl           crypto
-  --enable-x11grab           X11 grabbing through xlib (legacy, use xcb instead)
   --enable-zlib              compression [autodetect]
 
   The following libraries provide various hardware acceleration features:
@@ -1242,7 +1241,6 @@ EXTERNAL_LIBRARY_GPL_LIST="
     libx265
     libxavs
     libxvid
-    x11grab
 "
 
 EXTERNAL_LIBRARY_NONFREE_LIST="
@@ -2369,7 +2367,6 @@ sndio_outdev_deps="sndio_h"
 v4l2_indev_deps_any="linux_videodev2_h sys_videoio_h"
 vfwcap_indev_deps="capCreateCaptureWindow vfwcap_defines"
 vfwcap_indev_extralibs="-lavicap32"
-x11grab_indev_deps="x11grab"
 x11grab_xcb_indev_deps="libxcb"
 
 # protocols
@@ -4752,10 +4749,10 @@ fi
 
 check_lib X11/Xlib.h XOpenDisplay -lX11 && enable xlib
 
-if enabled libxcb || enabled x11grab && ! disabled libxcb; then
+if enabled libxcb; then
     check_pkg_config xcb-shape xcb/shape.h xcb_shape_rectangles || {
         enabled libxcb && die "ERROR: libxcb not found";
-    } && disable x11grab && enable libxcb
+    } && enable libxcb
 
     disabled libxcb_shm ||
         check_pkg_config xcb-shm xcb/shm.h xcb_shm_attach || {
@@ -4771,12 +4768,6 @@ if enabled libxcb || enabled x11grab && ! disabled libxcb; then
     add_extralibs "$xcb_event_libs $xcb_shm_libs $xcb_xfixes_libs"
 fi
 
-if enabled x11grab; then
-    enabled xlib || die "ERROR: Xlib not found"
-    require Xext X11/extensions/XShm.h XShmCreateImage -lXext
-    require Xfixes X11/extensions/Xfixes.h XFixesGetCursorImage -lXfixes
-fi
-
 enabled vaapi &&
     check_code cc "va/va.h" "vaCreateSurfaces(0, 0, 0, 0, 0, 0, 0, 0)" ||
     disable vaapi
diff --git a/libavdevice/Makefile b/libavdevice/Makefile
index b3b53da..a4c96ef 100644
--- a/libavdevice/Makefile
+++ b/libavdevice/Makefile
@@ -23,7 +23,6 @@ OBJS-$(CONFIG_SNDIO_INDEV)               += sndio_dec.o sndio.o
 OBJS-$(CONFIG_SNDIO_OUTDEV)              += sndio_enc.o sndio.o
 OBJS-$(CONFIG_V4L2_INDEV)                += v4l2.o
 OBJS-$(CONFIG_VFWCAP_INDEV)              += vfwcap.o
-OBJS-$(CONFIG_X11GRAB_INDEV)             += x11grab.o
 OBJS-$(CONFIG_X11GRAB_XCB_INDEV)         += xcbgrab.o
 
 # external libraries
diff --git a/libavdevice/alldevices.c b/libavdevice/alldevices.c
index 8439b5b..8541dba 100644
--- a/libavdevice/alldevices.c
+++ b/libavdevice/alldevices.c
@@ -58,7 +58,6 @@ void avdevice_register_all(void)
     REGISTER_INOUTDEV(SNDIO,            sndio);
     REGISTER_INDEV   (V4L2,             v4l2);
     REGISTER_INDEV   (VFWCAP,           vfwcap);
-    REGISTER_INDEV   (X11GRAB,          x11grab);
     REGISTER_INDEV   (X11GRAB_XCB,      x11grab_xcb);
 
     /* external libraries */
diff --git a/libavdevice/avdevice.h b/libavdevice/avdevice.h
index 39166a5..824ac52 100644
--- a/libavdevice/avdevice.h
+++ b/libavdevice/avdevice.h
@@ -36,7 +36,7 @@
  * (de)muxers in libavdevice are of the AVFMT_NOFILE type (they use their own
  * I/O functions). The filename passed to avformat_open_input() often does not
  * refer to an actually existing file, but has some special device-specific
- * meaning - e.g. for x11grab it is the display name.
+ * meaning - e.g. for x11grab_xcb it is the display name.
  *
  * To use libavdevice, simply call avdevice_register_all() to register all
  * compiled muxers and demuxers. They all use standard libavformat API.
diff --git a/libavdevice/x11grab.c b/libavdevice/x11grab.c
deleted file mode 100644
index 60e2560..0000000
--- a/libavdevice/x11grab.c
+++ /dev/null
@@ -1,647 +0,0 @@
-/*
- * X11 video grab interface
- *
- * This file is part of Libav.
- *
- * Libav integration:
- * Copyright (C) 2006 Clemens Fruhwirth <clemens at endorphin.org>
- *                    Edouard Gomez <ed.gomez at free.fr>
- *
- * This file contains code from grab.c:
- * Copyright (c) 2000-2001 Fabrice Bellard
- *
- * This file contains code from the xvidcap project:
- * Copyright (C) 1997-1998 Rasca, Berlin
- *               2003-2004 Karl H. Beckers, Frankfurt
- *
- * Libav is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * Libav 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Libav; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/**
- * @file
- * X11 frame device demuxer
- * @author Clemens Fruhwirth <clemens at endorphin.org>
- * @author Edouard Gomez <ed.gomez at free.fr>
- */
-
-#include "config.h"
-
-#include <time.h>
-#include <sys/shm.h>
-
-#include <X11/X.h>
-#include <X11/Xlib.h>
-#include <X11/Xlibint.h>
-#include <X11/Xproto.h>
-#include <X11/Xutil.h>
-
-#include <X11/extensions/shape.h>
-#include <X11/extensions/Xfixes.h>
-#include <X11/extensions/XShm.h>
-
-#include "libavutil/internal.h"
-#include "libavutil/log.h"
-#include "libavutil/opt.h"
-#include "libavutil/parseutils.h"
-#include "libavutil/time.h"
-
-#include "libavformat/avformat.h"
-#include "libavformat/internal.h"
-
-/** X11 device demuxer context */
-typedef struct X11GrabContext {
-    const AVClass *class;    /**< Class for private options. */
-    int frame_size;          /**< Size in bytes of a grabbed frame */
-    AVRational time_base;    /**< Time base */
-    int64_t time_frame;      /**< Current time */
-
-    char *video_size;        /**< String describing video size, set by a private option. */
-    int height;              /**< Height of the grab frame */
-    int width;               /**< Width of the grab frame */
-    int x_off;               /**< Horizontal top-left corner coordinate */
-    int y_off;               /**< Vertical top-left corner coordinate */
-
-    Display *dpy;            /**< X11 display from which x11grab grabs frames */
-    XImage *image;           /**< X11 image holding the grab */
-    int use_shm;             /**< !0 when using XShm extension */
-    XShmSegmentInfo shminfo; /**< When using XShm, keeps track of XShm info */
-    int draw_mouse;          /**< Set by a private option. */
-    int follow_mouse;        /**< Set by a private option. */
-    int show_region;         /**< set by a private option. */
-    char *framerate;         /**< Set by a private option. */
-
-    Window region_win;       /**< This is used by show_region option. */
-} X11GrabContext;
-
-#define REGION_WIN_BORDER 3
-
-/**
- * Draw grabbing region window
- *
- * @param s x11grab context
- */
-static void x11grab_draw_region_win(X11GrabContext *s)
-{
-    Display *dpy = s->dpy;
-    Window win   = s->region_win;
-    int screen = DefaultScreen(dpy);
-    GC gc = XCreateGC(dpy, win, 0, 0);
-
-    XSetForeground(dpy, gc, WhitePixel(dpy, screen));
-    XSetBackground(dpy, gc, BlackPixel(dpy, screen));
-    XSetLineAttributes(dpy, gc, REGION_WIN_BORDER, LineDoubleDash, 0, 0);
-    XDrawRectangle(dpy, win, gc, 1, 1,
-                   (s->width  + REGION_WIN_BORDER * 2) - 1 * 2 - 1,
-                   (s->height + REGION_WIN_BORDER * 2) - 1 * 2 - 1);
-    XFreeGC(dpy, gc);
-}
-
-/**
- * Initialize grabbing region window
- *
- * @param s x11grab context
- */
-static void x11grab_region_win_init(X11GrabContext *s)
-{
-    Display *dpy = s->dpy;
-    XRectangle rect;
-    XSetWindowAttributes attribs = { .override_redirect = True };
-    int screen = DefaultScreen(dpy);
-
-    s->region_win = XCreateWindow(dpy, RootWindow(dpy, screen),
-                                  s->x_off  - REGION_WIN_BORDER,
-                                  s->y_off  - REGION_WIN_BORDER,
-                                  s->width  + REGION_WIN_BORDER * 2,
-                                  s->height + REGION_WIN_BORDER * 2,
-                                  0, CopyFromParent,
-                                  InputOutput, CopyFromParent,
-                                  CWOverrideRedirect, &attribs);
-    rect.x      = 0;
-    rect.y      = 0;
-    rect.width  = s->width;
-    rect.height = s->height;
-    XShapeCombineRectangles(dpy, s->region_win,
-                            ShapeBounding, REGION_WIN_BORDER, REGION_WIN_BORDER,
-                            &rect, 1, ShapeSubtract, 0);
-    XMapWindow(dpy, s->region_win);
-    XSelectInput(dpy, s->region_win, ExposureMask | StructureNotifyMask);
-    x11grab_draw_region_win(s);
-}
-
-static int setup_shm(AVFormatContext *s, Display *dpy, XImage **image)
-{
-    X11GrabContext *g = s->priv_data;
-    int scr           = XDefaultScreen(dpy);
-    XImage *img       = XShmCreateImage(dpy, DefaultVisual(dpy, scr),
-                                        DefaultDepth(dpy, scr), ZPixmap, NULL,
-                                        &g->shminfo, g->width, g->height);
-
-    g->shminfo.shmid = shmget(IPC_PRIVATE, img->bytes_per_line * img->height,
-                              IPC_CREAT | 0777);
-
-    if (g->shminfo.shmid == -1) {
-        av_log(s, AV_LOG_ERROR, "Cannot get shared memory!\n");
-        return AVERROR(ENOMEM);
-    }
-
-    g->shminfo.shmaddr  = img->data = shmat(g->shminfo.shmid, 0, 0);
-    g->shminfo.readOnly = False;
-
-    if (!XShmAttach(dpy, &g->shminfo)) {
-        av_log(s, AV_LOG_ERROR, "Failed to attach shared memory!\n");
-        /* needs some better error subroutine :) */
-        return AVERROR(EIO);
-    }
-
-    *image = img;
-    return 0;
-}
-
-static int setup_mouse(Display *dpy, int screen)
-{
-    int ev_ret, ev_err;
-
-    if (XFixesQueryExtension(dpy, &ev_ret, &ev_err)) {
-        Window root = RootWindow(dpy, screen);
-        XFixesSelectCursorInput(dpy, root, XFixesDisplayCursorNotifyMask);
-        return 0;
-    }
-
-    return AVERROR(ENOSYS);
-}
-
-static int pixfmt_from_image(AVFormatContext *s, XImage *image, int *pix_fmt)
-{
-    av_log(s, AV_LOG_DEBUG,
-           "Image r 0x%.6lx g 0x%.6lx b 0x%.6lx and depth %i\n",
-           image->red_mask,
-           image->green_mask,
-           image->blue_mask,
-           image->bits_per_pixel);
-
-    switch (image->bits_per_pixel) {
-    case 8:
-        *pix_fmt =  AV_PIX_FMT_PAL8;
-        break;
-    case 16:
-        if (image->red_mask   == 0xf800 &&
-            image->green_mask == 0x07e0 &&
-            image->blue_mask  == 0x001f) {
-            *pix_fmt = AV_PIX_FMT_RGB565;
-        } else if (image->red_mask   == 0x7c00 &&
-                   image->green_mask == 0x03e0 &&
-                   image->blue_mask  == 0x001f) {
-            *pix_fmt = AV_PIX_FMT_RGB555;
-        }
-        break;
-    case 24:
-        if (image->red_mask   == 0xff0000 &&
-            image->green_mask == 0x00ff00 &&
-            image->blue_mask  == 0x0000ff) {
-            *pix_fmt = AV_PIX_FMT_BGR24;
-        } else if (image->red_mask   == 0x0000ff &&
-                   image->green_mask == 0x00ff00 &&
-                   image->blue_mask  == 0xff0000) {
-            *pix_fmt = AV_PIX_FMT_RGB24;
-        }
-        break;
-    case 32:
-        *pix_fmt = AV_PIX_FMT_RGB32;
-        break;
-    default:
-        av_log(s, AV_LOG_ERROR,
-               "XImages with RGB mask 0x%.6lx 0x%.6lx 0x%.6lx and depth %i "
-               "are currently not supported.\n",
-               image->red_mask,
-               image->green_mask,
-               image->blue_mask,
-               image->bits_per_pixel);
-
-        return AVERROR_PATCHWELCOME;
-    }
-
-    return 0;
-}
-
-/**
- * Initialize the x11 grab device demuxer (public device demuxer API).
- *
- * @param s1 Context from avformat core
- * @return <ul>
- *          <li>AVERROR(ENOMEM) no memory left</li>
- *          <li>AVERROR(EIO) other failure case</li>
- *          <li>0 success</li>
- *         </ul>
- */
-static int x11grab_read_header(AVFormatContext *s1)
-{
-    X11GrabContext *x11grab = s1->priv_data;
-    Display *dpy;
-    AVStream *st = NULL;
-    XImage *image;
-    int x_off = 0, y_off = 0, ret = 0, screen, use_shm;
-    char *param, *offset;
-    AVRational framerate;
-
-    param = av_strdup(s1->filename);
-    if (!param)
-        goto out;
-
-    offset = strchr(param, '+');
-    if (offset) {
-        sscanf(offset, "%d,%d", &x_off, &y_off);
-        x11grab->draw_mouse = !strstr(offset, "nomouse");
-        *offset = 0;
-    }
-
-    ret = av_parse_video_size(&x11grab->width, &x11grab->height,
-                              x11grab->video_size);
-    if (ret < 0) {
-        av_log(s1, AV_LOG_ERROR, "Couldn't parse video size.\n");
-        goto out;
-    }
-
-    ret = av_parse_video_rate(&framerate, x11grab->framerate);
-    if (ret < 0) {
-        av_log(s1, AV_LOG_ERROR, "Could not parse framerate: %s.\n",
-               x11grab->framerate);
-        goto out;
-    }
-    av_log(s1, AV_LOG_INFO,
-           "device: %s -> display: %s x: %d y: %d width: %d height: %d\n",
-           s1->filename, param, x_off, y_off, x11grab->width, x11grab->height);
-
-    dpy = XOpenDisplay(param);
-    if (!dpy) {
-        av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
-        ret = AVERROR(EIO);
-        goto out;
-    }
-
-    st = avformat_new_stream(s1, NULL);
-    if (!st) {
-        ret = AVERROR(ENOMEM);
-        goto out;
-    }
-    avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
-
-    screen = DefaultScreen(dpy);
-
-    if (x11grab->follow_mouse) {
-        int screen_w, screen_h;
-        Window w;
-
-        screen_w = DisplayWidth(dpy, screen);
-        screen_h = DisplayHeight(dpy, screen);
-        XQueryPointer(dpy, RootWindow(dpy, screen), &w, &w, &x_off, &y_off,
-                      &ret, &ret, &ret);
-        x_off -= x11grab->width / 2;
-        y_off -= x11grab->height / 2;
-        x_off  = FFMIN(FFMAX(x_off, 0), screen_w - x11grab->width);
-        y_off  = FFMIN(FFMAX(y_off, 0), screen_h - x11grab->height);
-        av_log(s1, AV_LOG_INFO,
-               "followmouse is enabled, resetting grabbing region to x: %d y: %d\n",
-               x_off, y_off);
-    }
-
-    use_shm = XShmQueryExtension(dpy);
-    av_log(s1, AV_LOG_INFO,
-           "shared memory extension %sfound\n", use_shm ? "" : "not ");
-
-    if (use_shm && setup_shm(s1, dpy, &image) < 0) {
-        av_log(s1, AV_LOG_WARNING, "Falling back to XGetImage\n");
-        use_shm = 0;
-    }
-
-    if (!use_shm) {
-        image = XGetImage(dpy, RootWindow(dpy, screen),
-                          x_off, y_off,
-                          x11grab->width, x11grab->height,
-                          AllPlanes, ZPixmap);
-    }
-
-    if (x11grab->draw_mouse && setup_mouse(dpy, screen) < 0) {
-        av_log(s1, AV_LOG_WARNING,
-               "XFixes not available, cannot draw the mouse cursor\n");
-        x11grab->draw_mouse = 0;
-    }
-
-    x11grab->frame_size = x11grab->width * x11grab->height * image->bits_per_pixel / 8;
-    x11grab->dpy        = dpy;
-    x11grab->time_base  = (AVRational) { framerate.den, framerate.num };
-    x11grab->time_frame = av_gettime() / av_q2d(x11grab->time_base);
-    x11grab->x_off      = x_off;
-    x11grab->y_off      = y_off;
-    x11grab->image      = image;
-    x11grab->use_shm    = use_shm;
-
-    ret = pixfmt_from_image(s1, image, &st->codecpar->format);
-    if (ret < 0)
-        goto out;
-
-    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
-    st->codecpar->codec_id   = AV_CODEC_ID_RAWVIDEO;
-    st->codecpar->width      = x11grab->width;
-    st->codecpar->height     = x11grab->height;
-    st->codecpar->bit_rate   = x11grab->frame_size * 1 / av_q2d(x11grab->time_base) * 8;
-
-    st->avg_frame_rate       = av_inv_q(x11grab->time_base);
-
-out:
-    av_free(param);
-    return ret;
-}
-
-/**
- * Paint a mouse pointer in an X11 image.
- *
- * @param image image to paint the mouse pointer to
- * @param s context used to retrieve original grabbing rectangle
- *          coordinates
- */
-static void paint_mouse_pointer(XImage *image, X11GrabContext *s)
-{
-    int x_off    = s->x_off;
-    int y_off    = s->y_off;
-    int width    = s->width;
-    int height   = s->height;
-    Display *dpy = s->dpy;
-    XFixesCursorImage *xcim;
-    int x, y;
-    int line, column;
-    int to_line, to_column;
-    int pixstride = image->bits_per_pixel >> 3;
-    /* Warning: in its insanity, xlib provides unsigned image data through a
-     * char* pointer, so we have to make it uint8_t to make things not break.
-     * Anyone who performs further investigation of the xlib API likely risks
-     * permanent brain damage. */
-    uint8_t *pix = image->data;
-
-    /* Code doesn't currently support 16-bit or PAL8 */
-    if (image->bits_per_pixel != 24 && image->bits_per_pixel != 32)
-        return;
-
-    xcim = XFixesGetCursorImage(dpy);
-    if (!xcim)
-        return;
-
-    x = xcim->x - xcim->xhot;
-    y = xcim->y - xcim->yhot;
-
-    to_line   = FFMIN((y + xcim->height), (height + y_off));
-    to_column = FFMIN((x + xcim->width),  (width  + x_off));
-
-    for (line = FFMAX(y, y_off); line < to_line; line++) {
-        for (column = FFMAX(x, x_off); column < to_column; column++) {
-            int xcim_addr  = (line  - y)     * xcim->width + column - x;
-            int image_addr = ((line - y_off) * width       + column - x_off) * pixstride;
-            int r          = (uint8_t)(xcim->pixels[xcim_addr] >>  0);
-            int g          = (uint8_t)(xcim->pixels[xcim_addr] >>  8);
-            int b          = (uint8_t)(xcim->pixels[xcim_addr] >> 16);
-            int a          = (uint8_t)(xcim->pixels[xcim_addr] >> 24);
-
-            if (a == 255) {
-                pix[image_addr + 0] = r;
-                pix[image_addr + 1] = g;
-                pix[image_addr + 2] = b;
-            } else if (a) {
-                /* pixel values from XFixesGetCursorImage come premultiplied by alpha */
-                pix[image_addr + 0] = r + (pix[image_addr + 0] * (255 - a) + 255 / 2) / 255;
-                pix[image_addr + 1] = g + (pix[image_addr + 1] * (255 - a) + 255 / 2) / 255;
-                pix[image_addr + 2] = b + (pix[image_addr + 2] * (255 - a) + 255 / 2) / 255;
-            }
-        }
-    }
-
-    XFree(xcim);
-    xcim = NULL;
-}
-
-/**
- * Read new data in the image structure.
- *
- * @param dpy X11 display to grab from
- * @param d
- * @param image Image where the grab will be put
- * @param x Top-Left grabbing rectangle horizontal coordinate
- * @param y Top-Left grabbing rectangle vertical coordinate
- * @return 0 if error, !0 if successful
- */
-static int xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
-{
-    xGetImageReply rep;
-    xGetImageReq *req;
-    long nbytes;
-
-    if (!image)
-        return 0;
-
-    LockDisplay(dpy);
-    GetReq(GetImage, req);
-
-    /* First set up the standard stuff in the request */
-    req->drawable  = d;
-    req->x         = x;
-    req->y         = y;
-    req->width     = image->width;
-    req->height    = image->height;
-    req->planeMask = (unsigned int)AllPlanes;
-    req->format    = ZPixmap;
-
-    if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
-        UnlockDisplay(dpy);
-        SyncHandle();
-        return 0;
-    }
-
-    nbytes = (long)rep.length << 2;
-    _XReadPad(dpy, image->data, nbytes);
-
-    UnlockDisplay(dpy);
-    SyncHandle();
-    return 1;
-}
-
-/**
- * Grab a frame from x11 (public device demuxer API).
- *
- * @param s1 Context from avformat core
- * @param pkt Packet holding the brabbed frame
- * @return frame size in bytes
- */
-static int x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
-{
-    X11GrabContext *s = s1->priv_data;
-    Display *dpy      = s->dpy;
-    XImage *image     = s->image;
-    int x_off         = s->x_off;
-    int y_off         = s->y_off;
-    int follow_mouse  = s->follow_mouse;
-    int screen, pointer_x, pointer_y, _, same_screen = 1;
-    Window w, root;
-    int64_t curtime, delay;
-    struct timespec ts;
-
-    /* Calculate the time of the next frame */
-    s->time_frame += INT64_C(1000000);
-
-    /* wait based on the frame rate */
-    for (;;) {
-        curtime = av_gettime();
-        delay   = s->time_frame * av_q2d(s->time_base) - curtime;
-        if (delay <= 0) {
-            if (delay < INT64_C(-1000000) * av_q2d(s->time_base))
-                s->time_frame += INT64_C(1000000);
-            break;
-        }
-        ts.tv_sec  = delay / 1000000;
-        ts.tv_nsec = (delay % 1000000) * 1000;
-        nanosleep(&ts, NULL);
-    }
-
-    pkt->data = image->data;
-    pkt->size = s->frame_size;
-    pkt->pts  = curtime;
-
-    screen = DefaultScreen(dpy);
-    root   = RootWindow(dpy, screen);
-
-    if (follow_mouse || s->draw_mouse)
-        same_screen = XQueryPointer(dpy, root, &w, &w,
-                                    &pointer_x, &pointer_y, &_, &_, &_);
-
-    if (follow_mouse && same_screen) {
-        int screen_w, screen_h;
-
-        screen_w = DisplayWidth(dpy, screen);
-        screen_h = DisplayHeight(dpy, screen);
-        if (follow_mouse == -1) {
-            // follow the mouse, put it at center of grabbing region
-            x_off += pointer_x - s->width / 2 - x_off;
-            y_off += pointer_y - s->height / 2 - y_off;
-        } else {
-            // follow the mouse, but only move the grabbing region when mouse
-            // reaches within certain pixels to the edge.
-            if (pointer_x > x_off + s->width - follow_mouse)
-                x_off += pointer_x - (x_off + s->width - follow_mouse);
-            else if (pointer_x < x_off + follow_mouse)
-                x_off -= (x_off + follow_mouse) - pointer_x;
-            if (pointer_y > y_off + s->height - follow_mouse)
-                y_off += pointer_y - (y_off + s->height - follow_mouse);
-            else if (pointer_y < y_off + follow_mouse)
-                y_off -= (y_off + follow_mouse) - pointer_y;
-        }
-        // adjust grabbing region position if it goes out of screen.
-        s->x_off = x_off = FFMIN(FFMAX(x_off, 0), screen_w - s->width);
-        s->y_off = y_off = FFMIN(FFMAX(y_off, 0), screen_h - s->height);
-
-        if (s->show_region && s->region_win)
-            XMoveWindow(dpy, s->region_win,
-                        s->x_off - REGION_WIN_BORDER,
-                        s->y_off - REGION_WIN_BORDER);
-    }
-
-    if (s->show_region && same_screen) {
-        if (s->region_win) {
-            XEvent evt = { .type = NoEventMask };
-            // Clean up the events, and do the initial draw or redraw.
-            while (XCheckMaskEvent(dpy, ExposureMask | StructureNotifyMask,
-                                   &evt))
-                ;
-            if (evt.type)
-                x11grab_draw_region_win(s);
-        } else {
-            x11grab_region_win_init(s);
-        }
-    }
-
-    if (s->use_shm) {
-        if (!XShmGetImage(dpy, root, image, x_off, y_off, AllPlanes))
-            av_log(s1, AV_LOG_INFO, "XShmGetImage() failed\n");
-    } else {
-        if (!xget_zpixmap(dpy, root, image, x_off, y_off))
-            av_log(s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
-    }
-
-    if (s->draw_mouse && same_screen)
-        paint_mouse_pointer(image, s);
-
-    return s->frame_size;
-}
-
-/**
- * Close x11 frame grabber (public device demuxer API).
- *
- * @param s1 Context from avformat core
- * @return 0 success, !0 failure
- */
-static int x11grab_read_close(AVFormatContext *s1)
-{
-    X11GrabContext *x11grab = s1->priv_data;
-
-    /* Detach cleanly from shared mem */
-    if (x11grab->use_shm) {
-        XShmDetach(x11grab->dpy, &x11grab->shminfo);
-        shmdt(x11grab->shminfo.shmaddr);
-        shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
-    }
-
-    /* Destroy X11 image */
-    if (x11grab->image) {
-        XDestroyImage(x11grab->image);
-        x11grab->image = NULL;
-    }
-
-    if (x11grab->region_win)
-        XDestroyWindow(x11grab->dpy, x11grab->region_win);
-
-    /* Free X11 display */
-    XCloseDisplay(x11grab->dpy);
-    return 0;
-}
-
-#define OFFSET(x) offsetof(X11GrabContext, x)
-#define DEC AV_OPT_FLAG_DECODING_PARAM
-static const AVOption options[] = {
-    { "grab_x", "Initial x coordinate.", OFFSET(x_off), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
-    { "grab_y", "Initial y coordinate.", OFFSET(y_off), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
-    { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = "vga"}, 0, 0, DEC },
-    { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "ntsc"}, 0, 0, DEC },
-    { "draw_mouse", "Draw the mouse pointer.", OFFSET(draw_mouse), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, DEC },
-    { "follow_mouse", "Move the grabbing region when the mouse pointer reaches within specified amount of pixels to the edge of region.",
-      OFFSET(follow_mouse), AV_OPT_TYPE_INT, { .i64 = 0 }, -1, INT_MAX, DEC, "follow_mouse" },
-    { "centered", "Keep the mouse pointer at the center of grabbing region when following.", 0, AV_OPT_TYPE_CONST, { .i64 = -1 }, INT_MIN, INT_MAX, DEC, "follow_mouse" },
-    { "show_region", "Show the grabbing region.", OFFSET(show_region), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, DEC },
-    { NULL },
-};
-
-static const AVClass x11_class = {
-    .class_name = "X11grab indev",
-    .item_name  = av_default_item_name,
-    .option     = options,
-    .version    = LIBAVUTIL_VERSION_INT,
-};
-
-/** x11 grabber device demuxer declaration */
-AVInputFormat ff_x11grab_demuxer = {
-    .name           = "x11grab",
-    .long_name      = NULL_IF_CONFIG_SMALL("X11grab"),
-    .priv_data_size = sizeof(X11GrabContext),
-    .read_header    = x11grab_read_header,
-    .read_packet    = x11grab_read_packet,
-    .read_close     = x11grab_read_close,
-    .flags          = AVFMT_NOFILE,
-    .priv_class     = &x11_class,
-};



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