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| − | This sample code will generate a thumbnail from any media.
| + | {{Lowercase}} |
| | + | Moved [http://git.videolan.org/?p=vlc.git;a=blob;f=doc/libvlc/vlc-thumb.c]. |
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| − | Using VLC 1.2 API (libvlc 5.1.0), last updated 2010, October 25th.
| + | [[Category:libVLC]] |
| − | | |
| − | It can be used by nautilus instead of totem-video-thumbnailer
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| − | /* Copyright [[User:Funman|Rafaël Carré]] (licence [http://en.wikipedia.org/wiki/WTFPL WTFPL]) */
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| − | <pre>
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| − | /* A video thumbnailer compatible with nautilus */
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| − | /* Copyright © 2007-2010 Rafaël Carré <funman@videolanorg> */
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| − | | |
| − | #include <assert.h>
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| − | #include <stdio.h>
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| − | #include <stdlib.h>
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| − | #include <string.h>
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| − | #include <unistd.h>
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| − | #include <locale.h>
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| − | | |
| − | #include <vlc/vlc.h>
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| − | | |
| − | /* gcc -pedantic -Wall -Werror -Wextra `pkg-config --cflags --libs libvlc` */
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| − | | |
| − | /* position at which the snapshot is taken */
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| − | #define VLC_THUMBNAIL_POSITION (30./100.)
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| − | | |
| − | static void usage(const char *name, int ret)
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| − | {
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| − | fprintf(stderr, "Usage: %s [-w width] <video> <output.png>\n", name);
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| − | exit(ret);
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| − | }
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| − | | |
| − | /* extracts options from command line */
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| − | static void cmdline(int argc, const char **argv, const char **in,
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| − | char **out, char **out_with_ext, int *w)
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| − | {
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| − | int idx = 1;
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| − | size_t len;
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| − | | |
| − | if (argc != 3 && argc != 5)
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| − | usage(argv[0], argc != 2 || strcmp(argv[1], "-h"));
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| − | | |
| − | *w = 0;
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| − | | |
| − | if (argc == 5) {
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| − | if (strcmp(argv[1], "-w"))
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| − | usage(argv[0], 1);
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| − | | |
| − | idx += 2; /* skip "-w width" */
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| − | *w = atoi(argv[2]);
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| − | }
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| − | | |
| − | *in = argv[idx++];
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| − | *out = strdup(argv[idx++]);
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| − | assert(*out);
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| − | | |
| − | len = strlen(*out);
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| − | if (len >= 4 && !strcmp(*out + len - 4, ".png")) {
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| − | *out_with_ext = *out;
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| − | return;
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| − | }
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| − | | |
| − | /* We need to add .png extension to filename,
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| − | * VLC relies on it to detect output format,
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| − | * and nautilus doesn't give filenames ending in .png */
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| − | | |
| − | *out_with_ext = malloc(len + sizeof ".png");
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| − | assert(*out_with_ext);
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| − | strcpy(*out_with_ext, *out);
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| − | strcat(*out_with_ext, ".png");
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| − | }
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| − | | |
| − | static libvlc_instance_t *create_libvlc(void)
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| − | {
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| − | static const char* const args[] = {
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| − | "--intf", "dummy", /* no interface */
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| − | "--vout", "dummy", /* we don't want video (output) */
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| − | "--no-audio", /* we don't want audio (decoding) */
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| − | "--no-video-title-show", /* nor the filename displayed */
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| − | "--no-stats", /* no stats */
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| − | "--no-sub-autodetect-file", /* we don't want subtitles */
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| − | "--no-inhibit", /* we don't want interfaces */
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| − | "--no-disable-screensaver", /* we don't want interfaces */
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| − | #if 0
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| − | "--verbose=2", /* full log */
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| − | #endif
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| − | };
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| − | | |
| − | return libvlc_new(sizeof args / sizeof *args, args);
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| − | }
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| − | | |
| − | static void callback(const libvlc_event_t *ev, void *param)
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| − | {
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| − | float new_position = ev->u.media_player_position_changed.new_position;
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| − | | |
| − | switch (ev->type) {
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| − | | |
| − | case libvlc_MediaPlayerPositionChanged:
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| − | if (new_position >= VLC_THUMBNAIL_POSITION * .9) { /* 90% margin */
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| − | *(int*)param = 1;
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| − | }
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| − | break;
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| − | case libvlc_MediaPlayerSnapshotTaken:
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| − | *(int*)param = 1;
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| − | break;
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| − | | |
| − | default:
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| − | assert(0);
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| − | }
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| − | }
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| − | | |
| − | /* FIXME: should use pthread notification */
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| − | static void event_wait(const char *error, int *f)
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| − | {
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| − | #define VLC_THUMBNAIL_TIMEOUT 5.0 /* 5 secs */
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| − | #define VLC_THUMBNAIL_LOOP_STEP 0.2 /* 200 ms */
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| − | | |
| − | float max = VLC_THUMBNAIL_TIMEOUT;
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| − | while ((max -= VLC_THUMBNAIL_LOOP_STEP) > 0.) {
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| − | if (*f)
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| − | return;
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| − | | |
| − | usleep(VLC_THUMBNAIL_LOOP_STEP * 1000000);
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| − | }
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| − | | |
| − | fprintf(stderr,
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| − | "%s (timeout after %.2f secs!\n", error, VLC_THUMBNAIL_TIMEOUT);
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| − | exit(1);
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| − | }
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| − | | |
| − | static void set_position(libvlc_media_player_t *mp)
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| − | {
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| − | int f = 0;
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| − | libvlc_event_manager_t *em = libvlc_media_player_event_manager(mp);
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| − | assert(em);
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| − | | |
| − | libvlc_event_attach(em, libvlc_MediaPlayerPositionChanged, callback, &f);
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| − | libvlc_media_player_set_position(mp, VLC_THUMBNAIL_POSITION);
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| − | event_wait("Couldn't set position", &f);
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| − | libvlc_event_detach(em, libvlc_MediaPlayerPositionChanged, callback, &f);
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| − | }
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| − | | |
| − | static void snapshot(libvlc_media_player_t *mp, int width, char *out_with_ext)
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| − | {
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| − | int f = 0;
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| − | libvlc_event_manager_t *em = libvlc_media_player_event_manager(mp);
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| − | assert(em);
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| − | | |
| − | libvlc_event_attach(em, libvlc_MediaPlayerSnapshotTaken, callback, &f);
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| − | libvlc_video_take_snapshot(mp, 0, out_with_ext, width, 0);
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| − | event_wait("Snapshot has not been written", &f);
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| − | libvlc_event_detach(em, libvlc_MediaPlayerSnapshotTaken, callback, &f);
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| − | }
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| − | | |
| − | int main(int argc, const char **argv)
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| − | {
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| − | const char *in;
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| − | char *out, *out_with_ext;
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| − | int width;
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| − | libvlc_instance_t *libvlc;
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| − | libvlc_media_player_t *mp;
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| − | libvlc_media_t *m;
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| − | | |
| − | /* mandatory to support UTF-8 filenames (provided the locale is well set)*/
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| − | setlocale(LC_ALL, getenv("LANG"));
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| − | | |
| − | cmdline(argc, argv, &in, &out, &out_with_ext, &width);
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| − | | |
| − | /* starts vlc */
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| − | libvlc = create_libvlc();
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| − | assert(libvlc);
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| − | | |
| − | m = libvlc_media_new_path(libvlc, in);
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| − | assert(m);
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| − | | |
| − | mp = libvlc_media_player_new_from_media(m);
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| − | assert(mp);
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| − | | |
| − | libvlc_media_player_play(mp);
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| − | | |
| − | /* takes snapshot */
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| − | set_position(mp);
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| − | snapshot(mp, width, out_with_ext);
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| − | | |
| − | libvlc_media_player_stop(mp);
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| − | | |
| − | /* clean up */
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| − | if (out != out_with_ext) {
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| − | rename(out_with_ext, out);
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| − | free(out_with_ext);
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| − | }
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| − | free(out);
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| − | | |
| − | libvlc_media_player_release(mp);
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| − | libvlc_media_release(m);
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| − | libvlc_release(libvlc);
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| − | | |
| − | return 0;
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| − | }
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| − | }</pre>
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