1/*
2 * X11 video grab interface
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg integration:
7 * Copyright (C) 2006 Clemens Fruhwirth <clemens@endorphin.org>
8 *                    Edouard Gomez <ed.gomez@free.fr>
9 *
10 * This file contains code from grab.c:
11 * Copyright (c) 2000-2001 Fabrice Bellard
12 *
13 * This file contains code from the xvidcap project:
14 * Copyright (C) 1997-1998 Rasca, Berlin
15 *               2003-2004 Karl H. Beckers, Frankfurt
16 *
17 * FFmpeg is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * FFmpeg is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
25 * GNU General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with FFmpeg; if not, write to the Free Software
29 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 */
31
32/**
33 * @file libavdevice/x11grab.c
34 * X11 frame device demuxer by Clemens Fruhwirth <clemens@endorphin.org>
35 * and Edouard Gomez <ed.gomez@free.fr>.
36 */
37
38#include "config.h"
39#include "libavformat/avformat.h"
40#include <unistd.h>
41#include <fcntl.h>
42#include <sys/ioctl.h>
43#include <sys/time.h>
44#define _LINUX_TIME_H 1
45#include <time.h>
46#include <X11/X.h>
47#include <X11/Xlib.h>
48#include <X11/Xlibint.h>
49#include <X11/Xproto.h>
50#include <X11/Xutil.h>
51#include <sys/ipc.h>
52#include <sys/shm.h>
53#include <X11/extensions/XShm.h>
54
55/**
56 * X11 Device Demuxer context
57 */
58struct x11_grab
59{
60    int frame_size;          /**< Size in bytes of a grabbed frame */
61    AVRational time_base;    /**< Time base */
62    int64_t time_frame;      /**< Current time */
63
64    int height;              /**< Height of the grab frame */
65    int width;               /**< Width of the grab frame */
66    int x_off;               /**< Horizontal top-left corner coordinate */
67    int y_off;               /**< Vertical top-left corner coordinate */
68
69    Display *dpy;            /**< X11 display from which x11grab grabs frames */
70    XImage *image;           /**< X11 image holding the grab */
71    int use_shm;             /**< !0 when using XShm extension */
72    XShmSegmentInfo shminfo; /**< When using XShm, keeps track of XShm infos */
73    int mouse_warning_shown;
74};
75
76/**
77 * Initializes the x11 grab device demuxer (public device demuxer API).
78 *
79 * @param s1 Context from avformat core
80 * @param ap Parameters from avformat core
81 * @return <ul>
82 *          <li>AVERROR(ENOMEM) no memory left</li>
83 *          <li>AVERROR(EIO) other failure case</li>
84 *          <li>0 success</li>
85 *         </ul>
86 */
87static int
88x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
89{
90    struct x11_grab *x11grab = s1->priv_data;
91    Display *dpy;
92    AVStream *st = NULL;
93    int input_pixfmt;
94    XImage *image;
95    int x_off = 0;
96    int y_off = 0;
97    int use_shm;
98    char *param, *offset;
99
100    param = av_strdup(s1->filename);
101    offset = strchr(param, '+');
102    if (offset) {
103        sscanf(offset, "%d,%d", &x_off, &y_off);
104        *offset= 0;
105    }
106
107    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, ap->width, ap->height);
108
109    dpy = XOpenDisplay(param);
110    if(!dpy) {
111        av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
112        return AVERROR(EIO);
113    }
114
115    if (!ap || ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
116        av_log(s1, AV_LOG_ERROR, "AVParameters don't have video size and/or rate. Use -s and -r.\n");
117        return AVERROR(EIO);
118    }
119
120    st = av_new_stream(s1, 0);
121    if (!st) {
122        return AVERROR(ENOMEM);
123    }
124    av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
125
126    use_shm = XShmQueryExtension(dpy);
127    av_log(s1, AV_LOG_INFO, "shared memory extension %s found\n", use_shm ? "" : "not");
128
129    if(use_shm) {
130        int scr = XDefaultScreen(dpy);
131        image = XShmCreateImage(dpy,
132                                DefaultVisual(dpy, scr),
133                                DefaultDepth(dpy, scr),
134                                ZPixmap,
135                                NULL,
136                                &x11grab->shminfo,
137                                ap->width, ap->height);
138        x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
139                                        image->bytes_per_line * image->height,
140                                        IPC_CREAT|0777);
141        if (x11grab->shminfo.shmid == -1) {
142            av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
143            return AVERROR(ENOMEM);
144        }
145        x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
146        x11grab->shminfo.readOnly = False;
147
148        if (!XShmAttach(dpy, &x11grab->shminfo)) {
149            av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
150            /* needs some better error subroutine :) */
151            return AVERROR(EIO);
152        }
153    } else {
154        image = XGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)),
155                          x_off,y_off,
156                          ap->width,ap->height,
157                          AllPlanes, ZPixmap);
158    }
159
160    switch (image->bits_per_pixel) {
161    case 8:
162        av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
163        input_pixfmt = PIX_FMT_PAL8;
164        break;
165    case 16:
166        if (       image->red_mask   == 0xf800 &&
167                   image->green_mask == 0x07e0 &&
168                   image->blue_mask  == 0x001f ) {
169            av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
170            input_pixfmt = PIX_FMT_RGB565;
171        } else if (image->red_mask   == 0x7c00 &&
172                   image->green_mask == 0x03e0 &&
173                   image->blue_mask  == 0x001f ) {
174            av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
175            input_pixfmt = PIX_FMT_RGB555;
176        } else {
177            av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
178            av_log(s1, AV_LOG_ERROR, "color masks: r 0x%.6lx g 0x%.6lx b 0x%.6lx\n", image->red_mask, image->green_mask, image->blue_mask);
179            return AVERROR(EIO);
180        }
181        break;
182    case 24:
183        if (        image->red_mask   == 0xff0000 &&
184                    image->green_mask == 0x00ff00 &&
185                    image->blue_mask  == 0x0000ff ) {
186            input_pixfmt = PIX_FMT_BGR24;
187        } else if ( image->red_mask   == 0x0000ff &&
188                    image->green_mask == 0x00ff00 &&
189                    image->blue_mask  == 0xff0000 ) {
190            input_pixfmt = PIX_FMT_RGB24;
191        } else {
192            av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
193            av_log(s1, AV_LOG_ERROR, "color masks: r 0x%.6lx g 0x%.6lx b 0x%.6lx\n", image->red_mask, image->green_mask, image->blue_mask);
194            return AVERROR(EIO);
195        }
196        break;
197    case 32:
198#if 0
199        GetColorInfo (image, &c_info);
200        if ( c_info.alpha_mask == 0xff000000 && image->green_mask == 0x0000ff00) {
201            /* byte order is relevant here, not endianness
202             * endianness is handled by avcodec, but atm no such thing
203             * as having ABGR, instead of ARGB in a word. Since we
204             * need this for Solaris/SPARC, but need to do the conversion
205             * for every frame we do it outside of this loop, cf. below
206             * this matches both ARGB32 and ABGR32 */
207            input_pixfmt = PIX_FMT_ARGB32;
208        }  else {
209            av_log(s1, AV_LOG_ERROR,"image depth %i not supported ... aborting\n", image->bits_per_pixel);
210            return AVERROR(EIO);
211        }
212#endif
213        input_pixfmt = PIX_FMT_RGB32;
214        break;
215    default:
216        av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
217        return -1;
218    }
219
220    x11grab->frame_size = ap->width * ap->height * image->bits_per_pixel/8;
221    x11grab->dpy = dpy;
222    x11grab->width = ap->width;
223    x11grab->height = ap->height;
224    x11grab->time_base  = ap->time_base;
225    x11grab->time_frame = av_gettime() / av_q2d(ap->time_base);
226    x11grab->x_off = x_off;
227    x11grab->y_off = y_off;
228    x11grab->image = image;
229    x11grab->use_shm = use_shm;
230    x11grab->mouse_warning_shown = 0;
231
232    st->codec->codec_type = CODEC_TYPE_VIDEO;
233    st->codec->codec_id = CODEC_ID_RAWVIDEO;
234    st->codec->width = ap->width;
235    st->codec->height = ap->height;
236    st->codec->pix_fmt = input_pixfmt;
237    st->codec->time_base = ap->time_base;
238    st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(ap->time_base) * 8;
239
240    return 0;
241}
242
243/**
244 * Get pointer coordinates from X11.
245 *
246 * @param x Integer where horizontal coordinate will be returned
247 * @param y Integer where vertical coordinate will be returned
248 * @param dpy X11 display from where pointer coordinates are retrieved
249 * @param s1 Context used for logging errors if necessary
250 */
251static void
252get_pointer_coordinates(int *x, int *y, Display *dpy, AVFormatContext *s1)
253{
254    Window mrootwindow, childwindow;
255    int dummy;
256
257    mrootwindow = DefaultRootWindow(dpy);
258
259    if (XQueryPointer(dpy, mrootwindow, &mrootwindow, &childwindow,
260                      x, y, &dummy, &dummy, (unsigned int*)&dummy)) {
261    } else {
262        struct x11_grab *s = s1->priv_data;
263        if (!s->mouse_warning_shown) {
264            av_log(s1, AV_LOG_INFO, "couldn't find mouse pointer\n");
265            s->mouse_warning_shown = 1;
266        }
267        *x = -1;
268        *y = -1;
269    }
270}
271
272/**
273 * Mouse painting helper function that applies an 'and' and 'or' mask pair to
274 * '*dst' pixel. It actually draws a mouse pointer pixel to grabbed frame.
275 *
276 * @param dst Destination pixel
277 * @param and Part of the mask that must be applied using a bitwise 'and'
278 *            operator
279 * @param or  Part of the mask that must be applied using a bitwise 'or'
280 *            operator
281 * @param bits_per_pixel Bits per pixel used in the grabbed image
282 */
283static void inline
284apply_masks(uint8_t *dst, int and, int or, int bits_per_pixel)
285{
286    switch (bits_per_pixel) {
287    case 32:
288        *(uint32_t*)dst = (*(uint32_t*)dst & and) | or;
289        break;
290    case 16:
291        *(uint16_t*)dst = (*(uint16_t*)dst & and) | or;
292        break;
293    case 8:
294        *dst = !!or;
295        break;
296    }
297}
298
299/**
300 * Paints a mouse pointer in an X11 image.
301 *
302 * @param image image to paint the mouse pointer to
303 * @param s context used to retrieve original grabbing rectangle
304 *          coordinates
305 * @param x Mouse pointer coordinate
306 * @param y Mouse pointer coordinate
307 */
308static void
309paint_mouse_pointer(XImage *image, struct x11_grab *s, int x, int y)
310{
311    /* 16x20x1bpp bitmap for the black channel of the mouse pointer */
312    static const uint16_t const mousePointerBlack[] =
313        {
314            0x0000, 0x0003, 0x0005, 0x0009, 0x0011,
315            0x0021, 0x0041, 0x0081, 0x0101, 0x0201,
316            0x03c1, 0x0049, 0x0095, 0x0093, 0x0120,
317            0x0120, 0x0240, 0x0240, 0x0380, 0x0000
318        };
319
320    /* 16x20x1bpp bitmap for the white channel of the mouse pointer */
321    static const uint16_t const mousePointerWhite[] =
322        {
323            0x0000, 0x0000, 0x0002, 0x0006, 0x000e,
324            0x001e, 0x003e, 0x007e, 0x00fe, 0x01fe,
325            0x003e, 0x0036, 0x0062, 0x0060, 0x00c0,
326            0x00c0, 0x0180, 0x0180, 0x0000, 0x0000
327        };
328
329    int x_off = s->x_off;
330    int y_off = s->y_off;
331    int width = s->width;
332    int height = s->height;
333
334    if (   x - x_off >= 0 && x < width + x_off
335        && y - y_off >= 0 && y < height + y_off) {
336        uint8_t *im_data = (uint8_t*)image->data;
337        int bytes_per_pixel;
338        int line;
339        int masks;
340
341        /* Select correct masks and pixel size */
342        if (image->bits_per_pixel == 8) {
343            masks = 1;
344        } else {
345            masks = (image->red_mask|image->green_mask|image->blue_mask);
346        }
347        bytes_per_pixel = image->bits_per_pixel>>3;
348
349        /* Shift to right line */
350        im_data += image->bytes_per_line * (y - y_off);
351        /* Shift to right pixel in the line */
352        im_data += bytes_per_pixel * (x - x_off);
353
354        /* Draw the cursor - proper loop */
355        for (line = 0; line < FFMIN(20, (y_off + height) - y); line++) {
356            uint8_t *cursor = im_data;
357            int column;
358            uint16_t bm_b;
359            uint16_t bm_w;
360
361            bm_b = mousePointerBlack[line];
362            bm_w = mousePointerWhite[line];
363
364            for (column = 0; column < FFMIN(16, (x_off + width) - x); column++) {
365                apply_masks(cursor, ~(masks*(bm_b&1)), masks*(bm_w&1),
366                            image->bits_per_pixel);
367                cursor += bytes_per_pixel;
368                bm_b >>= 1;
369                bm_w >>= 1;
370            }
371            im_data += image->bytes_per_line;
372        }
373    }
374}
375
376
377/**
378 * Reads new data in the image structure.
379 *
380 * @param dpy X11 display to grab from
381 * @param d
382 * @param image Image where the grab will be put
383 * @param x Top-Left grabbing rectangle horizontal coordinate
384 * @param y Top-Left grabbing rectangle vertical coordinate
385 * @return 0 if error, !0 if successful
386 */
387static int
388xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
389{
390    xGetImageReply rep;
391    xGetImageReq *req;
392    long nbytes;
393
394    if (!image) {
395        return 0;
396    }
397
398    LockDisplay(dpy);
399    GetReq(GetImage, req);
400
401    /* First set up the standard stuff in the request */
402    req->drawable = d;
403    req->x = x;
404    req->y = y;
405    req->width = image->width;
406    req->height = image->height;
407    req->planeMask = (unsigned int)AllPlanes;
408    req->format = ZPixmap;
409
410    if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
411        UnlockDisplay(dpy);
412        SyncHandle();
413        return 0;
414    }
415
416    nbytes = (long)rep.length << 2;
417    _XReadPad(dpy, image->data, nbytes);
418
419    UnlockDisplay(dpy);
420    SyncHandle();
421    return 1;
422}
423
424/**
425 * Grabs a frame from x11 (public device demuxer API).
426 *
427 * @param s1 Context from avformat core
428 * @param pkt Packet holding the brabbed frame
429 * @return frame size in bytes
430 */
431static int
432x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
433{
434    struct x11_grab *s = s1->priv_data;
435    Display *dpy = s->dpy;
436    XImage *image = s->image;
437    int x_off = s->x_off;
438    int y_off = s->y_off;
439
440    int64_t curtime, delay;
441    struct timespec ts;
442
443    /* Calculate the time of the next frame */
444    s->time_frame += INT64_C(1000000);
445
446    /* wait based on the frame rate */
447    for(;;) {
448        curtime = av_gettime();
449        delay = s->time_frame * av_q2d(s->time_base) - curtime;
450        if (delay <= 0) {
451            if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
452                s->time_frame += INT64_C(1000000);
453            }
454            break;
455        }
456        ts.tv_sec = delay / 1000000;
457        ts.tv_nsec = (delay % 1000000) * 1000;
458        nanosleep(&ts, NULL);
459    }
460
461    if (av_new_packet(pkt, s->frame_size) < 0) {
462        return AVERROR(EIO);
463    }
464
465    pkt->pts = curtime;
466
467    if(s->use_shm) {
468        if (!XShmGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off, AllPlanes)) {
469            av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n");
470        }
471    } else {
472        if (!xget_zpixmap(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off)) {
473            av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
474        }
475    }
476
477    {
478        int pointer_x, pointer_y;
479        get_pointer_coordinates(&pointer_x, &pointer_y, dpy, s1);
480        paint_mouse_pointer(image, s, pointer_x, pointer_y);
481    }
482
483
484    /* XXX: avoid memcpy */
485    memcpy(pkt->data, image->data, s->frame_size);
486    return s->frame_size;
487}
488
489/**
490 * Closes x11 frame grabber (public device demuxer API).
491 *
492 * @param s1 Context from avformat core
493 * @return 0 success, !0 failure
494 */
495static int
496x11grab_read_close(AVFormatContext *s1)
497{
498    struct x11_grab *x11grab = s1->priv_data;
499
500    /* Detach cleanly from shared mem */
501    if (x11grab->use_shm) {
502        XShmDetach(x11grab->dpy, &x11grab->shminfo);
503        shmdt(x11grab->shminfo.shmaddr);
504        shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
505    }
506
507    /* Destroy X11 image */
508    if (x11grab->image) {
509        XDestroyImage(x11grab->image);
510        x11grab->image = NULL;
511    }
512
513    /* Free X11 display */
514    XCloseDisplay(x11grab->dpy);
515    return 0;
516}
517
518/** x11 grabber device demuxer declaration */
519AVInputFormat x11_grab_device_demuxer =
520{
521    "x11grab",
522    NULL_IF_CONFIG_SMALL("X11grab"),
523    sizeof(struct x11_grab),
524    NULL,
525    x11grab_read_header,
526    x11grab_read_packet,
527    x11grab_read_close,
528    .flags = AVFMT_NOFILE,
529};
530