Screen-shot tools: root2jpg and root2xpm

Question

Hi folks (new kid in town...)
Saw this sub-board in the forum & spent the next few evenings browsing all the very nifty projects you all have created, some innovative stuff so... I thought I'd add my own contributions to the mix =)
Here are two routines to take screen-shots, the 1st outputs a compressed JPG, & the 2nd a pixmap in XPM format.
But first an example... here's a JPG taken with root2jpg.
These could easily be hard-coded into for instance config.h in dwm, or a script with xbindkeys where either called a modifier and say the print-screen key (XK_Print).
Since I'm not yet running Arch, I can't roll up any packages (any takers?) At any rate, hope you all can use them!
roo2jpg v0.98 [c]2012 Topcat Software LLC.
http://www.topcat.hypermart.net/index.html
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
compilation: gcc -Wall -Werror root2jpg.c -o root2jpg -lX11 -ljpeg
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <jpeglib.h>
int exitmsg(int e) {
char buf[256]; // buffer for error messages
switch (e) {
case 1:
sprintf(buf, "value must be from 1 to 59");
break;
case 2:
sprintf(buf, "error opening display");
break;
case 3:
sprintf(buf, "error obtaining image");
break;
case 4:
sprintf(buf, "error failed to open file");
break;
fprintf(stderr, "roo2jpg: %s...\n", buf);
return 1;
int write_jpeg(XImage *img, const char* filename) {
FILE* fp;
unsigned long pixel;
int x, y;
char* tmp;
struct jpeg_compress_struct cinfo;
struct jpeg_error_mgr jerr;
JSAMPROW row_ptr;
fp = fopen(filename, "wb");
if (!fp) return 1;
// parse RGB values into tmp
tmp = malloc(sizeof(char)*3*img->width*img->height);
for (y = 0; y < img->height; y++) {
for (x = 0; x < img->width; x++) {
pixel = XGetPixel(img,x,y);
tmp[y*img->width*3+x*3+0] = (pixel>>16); // red
tmp[y*img->width*3+x*3+1] = ((pixel&0x00ff00)>>8); // green
tmp[y*img->width*3+x*3+2] = (pixel&0x0000ff); // blue
// fill in jpg structures
cinfo.err = jpeg_std_error(&jerr);
jpeg_create_compress(&cinfo);
jpeg_stdio_dest(&cinfo, fp);
cinfo.image_width = img->width;
cinfo.image_height = img->height;
cinfo.input_components = 3;
cinfo.in_color_space = JCS_RGB;
jpeg_set_defaults(&cinfo);
jpeg_set_quality(&cinfo, 85, TRUE);
jpeg_start_compress(&cinfo, TRUE);
// iterate through each scanline writing results to file
while (cinfo.next_scanline < cinfo.image_height) {
row_ptr = (JSAMPROW) &tmp[cinfo.next_scanline*\
(img->depth>>3)*img->width];
jpeg_write_scanlines(&cinfo, &row_ptr, 1);
// clean up
free(tmp);
jpeg_finish_compress(&cinfo);
fclose(fp);
return 0;
int syntax(void) {
system("clear");
printf("%s","\n\n\
roo2jpg screen-shot tool v0.98 [c]2012 Topcat Software LLC.\n\n\
syntax: roo2jpg [-s seconds] [-f file.jpg]\n\n\
where...\n\n\
-s specifies sleep in secs. (1 to 59)\n\n\
-f specifies filename\n\n");
return 0;
int main(int argc, char *argv[]) {
if (argc < 5 || argc > 5) return syntax(); // bad syntax return
int x = strcmp(argv[1], "-s"); // -s option
int y = strcmp(argv[3], "-f"); // -f option
if (x || y) return syntax(); // bad syntax return
int n = atoi(argv[2]); // number of seconds to sleep
if (n < 1 || n > 59) return exitmsg(1); // out of range return error msg
sleep(n); // zzz... n seconds
Display *dpy = XOpenDisplay(0); // attempt to open display
if (dpy == NULL) return exitmsg(2); // else return error
Window root = RootWindow(dpy,DefaultScreen(dpy)); // get root window
XWindowAttributes rootAttributes; // and then...
XGetWindowAttributes(dpy, root, &rootAttributes); // acquire attributes
XImage *img = XGetImage(dpy,root,0,0,\
rootAttributes.width, \
rootAttributes.height, \
XAllPlanes(),ZPixmap); // nab XImage of root window
if (img == NULL) { // if XGetImage() failed
XCloseDisplay(dpy); // close display and
return exitmsg(3); // return error
} else {
x = write_jpeg(img, argv[4]); // write jpg
XDestroyImage(img); // release memory
if (x != 0) { // if libjpg failed
XCloseDisplay(dpy); // close display and
return exitmsg(4); // return error
XCloseDisplay(dpy); // close display and
return 0; // bring it on home
// eof
root2xpm v0.99 [c]2012 Topcat Software LLC.
http://www.topcat.hypermart.net/index.html
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
compilation: gcc -Wall -Werror root2xpm.c -o root2xpm -lX11 -lXpm
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <X11/Xlib.h>
#include </usr/include/X11/xpm.h>
int exitmsg(int e) {
char buf[256]; // buffer for error messages
switch (e) {
case 1:
sprintf(buf, "value must be from 1 to 59");
break;
case 2:
sprintf(buf, "error opening display");
break;
case 3:
sprintf(buf, "error obtaining image");
break;
case 4:
sprintf(buf, "libxpm error");
break;
fprintf(stderr, "root2xpm: %s...\n", buf);
return 1;
int syntax(void) {
system("clear");
printf("%s","\n\n\
root2xpm screen-shot tool v0.99 [c]2012 Topcat Software LLC.\n\n\
syntax: root2xpm [-s seconds] [-f file.xpm]\n\n\
where...\n\n\
-s specifies sleep in secs. (1 to 59)\n\n\
-f specifies filename\n\n");
return 0;
int main(int argc, char *argv[]) {
if (argc < 5 || argc > 5) return syntax(); // bad syntax return
int x = strcmp(argv[1], "-s"); // -s option
int y = strcmp(argv[3], "-f"); // -f option
if (x || y) return syntax(); // bad syntax return
int n = atoi(argv[2]); // number of seconds to sleep
if (n < 1 || n > 59) return exitmsg(1); // out of range return error msg
sleep(n); // zzz... n seconds
Display *dpy = XOpenDisplay(0); // attempt to open display
if (dpy == NULL) return exitmsg(2); // else return error
Window root = RootWindow(dpy,DefaultScreen(dpy)); // get root window
XWindowAttributes rootAttributes; // and then...
XGetWindowAttributes(dpy, root, &rootAttributes); // acquire attributes
XImage *img = XGetImage(dpy,root,0,0,\
rootAttributes.width, \
rootAttributes.height, \
XAllPlanes(),ZPixmap); // nab XImage of root window
if (img == NULL) { // if XGetImage() failed
XCloseDisplay(dpy); // close display and
return exitmsg(3); // return error
} else {
x = XpmWriteFileFromImage(dpy,argv[4],img,0, NULL); // write xpm
XDestroyImage(img); // release memory
if (x == XpmOpenFailed) { // if libxpm failed
XCloseDisplay(dpy); // close display and
return exitmsg(4); // return error
XCloseDisplay(dpy); // close display and
return 0; // bring it on home
// eof
Last edited by topcat-software (2011-12-24 17:20:24)

Answer 1

topcat-software:
Welcome to Arch.  I hope you make the transition soon.  Your picture is a bit outside of our policy with regards to size.  I mostly concern myself with the byte count because many of our users are bandwidth limited.   As moderator, I would generally convert that to a link so that it is not displayed in-line.  But hey, it is the day before Christmas and I am in a good mood
The preferred method is to create a link to the full size picture, and inside that link, in-line a thumbnail so that readers can see the thumb, and click through it, if they wish.
Kind of like this : [ url=link to the big picture ][ img=link to the thumbnail [ /img ][ /url ]
Without the spaces to "break" the BBCode (of course).