libavformat/framehook.c

   1 /*
   2  * Video processing hooks
   3  * Copyright (c) 2000, 2001 Fabrice Bellard.
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21 #include <errno.h>
  22 #include "config.h"
  23 #include "avformat.h"
  24 #include "framehook.h"
  25
  26 #ifdef HAVE_DLFCN_H
  27 #include <dlfcn.h>
  28 #endif
  29
  30
  31 typedef struct FrameHookEntry {
  32     struct FrameHookEntry *next;
  33     FrameHookConfigureFn Configure;
  34     FrameHookProcessFn Process;
  35     FrameHookReleaseFn Release;
  36     void *ctx;
  37 } FrameHookEntry;
  38
  39 static FrameHookEntry *first_hook;
  40
  41 /* Returns 0 on OK */
  42 int frame_hook_add(int argc, char *argv[])
  43 {
  44 #ifdef CONFIG_VHOOK
  45     void *loaded;
  46     FrameHookEntry *fhe, **fhep;
  47
  48     if (argc < 1) {
  49         return ENOENT;
  50     }
  51
  52     loaded = dlopen(argv[0], RTLD_NOW);
  53     if (!loaded) {
  54         av_log(NULL, AV_LOG_ERROR, "%s\n", dlerror());
  55         return -1;
  56     }
  57
  58     fhe = av_mallocz(sizeof(*fhe));
  59     if (!fhe) {
  60         return AVERROR(ENOMEM);
  61     }
  62
  63     fhe->Configure = dlsym(loaded, "Configure");
  64     fhe->Process = dlsym(loaded, "Process");
  65     fhe->Release = dlsym(loaded, "Release");    /* Optional */
  66
  67     if (!fhe->Process) {
  68         av_log(NULL, AV_LOG_ERROR, "Failed to find Process entrypoint in %s\n", argv[0]);
  69         return AVERROR(ENOENT);
  70     }
  71
  72     if (!fhe->Configure && argc > 1) {
  73         av_log(NULL, AV_LOG_ERROR, "Failed to find Configure entrypoint in %s\n", argv[0]);
  74         return AVERROR(ENOENT);
  75     }
  76
  77     if (argc > 1 || fhe->Configure) {
  78         if (fhe->Configure(&fhe->ctx, argc, argv)) {
  79             av_log(NULL, AV_LOG_ERROR, "Failed to Configure %s\n", argv[0]);
  80             return AVERROR(EINVAL);
  81         }
  82     }
  83
  84     for (fhep = &first_hook; *fhep; fhep = &((*fhep)->next)) {
  85     }
  86
  87     *fhep = fhe;
  88
  89     return 0;
  90 #else
  91     av_log(NULL, AV_LOG_ERROR, "Video hooking not compiled into this version\n");
  92     return 1;
  93 #endif
  94 }
  95
  96 void frame_hook_process(AVPicture *pict, enum PixelFormat pix_fmt, int width, int height, int64_t pts)
  97 {
  98     if (first_hook) {
  99         FrameHookEntry *fhe;
 100
 101         for (fhe = first_hook; fhe; fhe = fhe->next) {
 102             fhe->Process(fhe->ctx, pict, pix_fmt, width, height, pts);
 103         }
 104     }
 105 }
 106
 107 void frame_hook_release(void)
 108 {
 109     FrameHookEntry *fhe;
 110     FrameHookEntry *fhenext;
 111
 112     for (fhe = first_hook; fhe; fhe = fhenext) {
 113         fhenext = fhe->next;
 114         if (fhe->Release)
 115             fhe->Release(fhe->ctx);
 116         av_free(fhe);
 117     }
 118
 119     first_hook = NULL;
 120 }