imlib2.c

ffmpeg的完整源代码和作者自己写的文档。不但有在Linux的工程哦

/*
 * imlib2 based hook
 * Copyright (c) 2002 Philip Gladstone
 *
 * This module is very much intended as an example of what could be done.
 *
 * One caution is that this is an expensive process -- in particular the
 * conversion of the image into RGB and back is time consuming. For some
 * special cases -- e.g. painting black text -- it would be faster to paint
 * the text into a bitmap and then combine it directly into the YUV
 * image. However, this code is fast enough to handle 10 fps of 320x240 on a
 * 900MHz Duron in maybe 15% of the CPU.

 * See further statistics on Pentium4, 3GHz, FFMpeg is SVN-r6798
 * Input movie is 20.2 seconds of PAL DV on AVI
 * Output movie is DVD compliant VOB.
 *
   ffmpeg -i input.avi -target pal-dvd out.vob
   #   13.516s  just transcode
   ffmpeg -i input.avi -vhook /usr/local/bin/vhook/null.dll -target pal-dvd out.vob
   #   23.546s  transcode and img_convert
   ffmpeg -i input.avi -vhook \
     'vhook/imlib2.dll -c red -F Vera/20 -x 150-0.5*N -y 70+0.25*N -t Hello_person' \
     -target pal-dvd out.vob
   #   21.454s  transcode, img_convert and move text around
   ffmpeg -i input.avi -vhook \
     'vhook/imlib2.dll -x 150-0.5*N -y 70+0.25*N -i /usr/share/imlib2/data/images/bulb.png' \
     -target pal-dvd out.vob
   #   20.828s  transcode, img_convert and move image around
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "framehook.h"
#include "swscale.h"

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>
#undef time
#include <sys/time.h>
#include <time.h>
#include <Imlib2.h>
#include "eval.h"

const char *const_names[]={
    "PI",
    "E",
    "N",  // frame number (starting at zero)
    "H",  // frame height
    "W",  // frame width
    "h",  // image height
    "w",  // image width
    "X",  // previous x
    "Y",  // previous y
    NULL
};

static int sws_flags = SWS_BICUBIC;

typedef struct {
    int dummy;
    Imlib_Font fn;
    char *text;
    char *file;
    int r, g, b, a;
    AVEvalExpr *eval_r, *eval_g, *eval_b, *eval_a;
    char *expr_R, *expr_G, *expr_B, *expr_A;
    int eval_colors;
    double x, y;
    char *fileImage;
    struct _CachedImage *cache;
    Imlib_Image imageOverlaid;
    AVEvalExpr *eval_x, *eval_y;
    char *expr_x, *expr_y;
    int frame_number;
    int imageOverlaid_width, imageOverlaid_height;

    // This vhook first converts frame to RGB ...
    struct SwsContext *toRGB_convert_ctx;
    // ... and then converts back frame from RGB to initial format
    struct SwsContext *fromRGB_convert_ctx;
} ContextInfo;

typedef struct _CachedImage {
    struct _CachedImage *next;
    Imlib_Image image;
    int width;
    int height;
} CachedImage;

void Release(void *ctx)
{
    ContextInfo *ci;
    ci = (ContextInfo *) ctx;

    if (ci->cache) {
        imlib_context_set_image(ci->cache->image);
        imlib_free_image();
        av_free(ci->cache);
    }
    if (ctx) {
        if (ci->imageOverlaid) {
            imlib_context_set_image(ci->imageOverlaid);
            imlib_free_image();
        }
        ff_eval_free(ci->eval_x);
        ff_eval_free(ci->eval_y);
        ff_eval_free(ci->eval_r);
        ff_eval_free(ci->eval_g);
        ff_eval_free(ci->eval_b);
        ff_eval_free(ci->eval_a);

        av_free(ci->expr_x);
        av_free(ci->expr_y);
        av_free(ci->expr_R);
        av_free(ci->expr_G);
        av_free(ci->expr_B);
        av_free(ci->expr_A);
        sws_freeContext(ci->toRGB_convert_ctx);
        sws_freeContext(ci->fromRGB_convert_ctx);
        av_free(ctx);
    }
}

int Configure(void **ctxp, int argc, char *argv[])
{
    int c;
    ContextInfo *ci;
    char *rgbtxt = 0;
    char *font = "LucidaSansDemiBold/16";
    char *fp = getenv("FONTPATH");
    char *color = 0;
    FILE *f;
    char *p;
    char *error;

    *ctxp = av_mallocz(sizeof(ContextInfo));
    ci = (ContextInfo *) *ctxp;

    ci->x = 0.0;
    ci->y = 0.0;
    ci->expr_x = "0.0";
    ci->expr_y = "0.0";

    optind = 0;

    /* Use ':' to split FONTPATH */
    if (fp)
        while (p = strchr(fp, ':')) {
            *p = 0;
            imlib_add_path_to_font_path(fp);
            fp = p + 1;
        }
    if ((fp) && (*fp))
        imlib_add_path_to_font_path(fp);


    while ((c = getopt(argc, argv, "R:G:B:A:C:c:f:F:t:x:y:i:")) > 0) {
        switch (c) {
            case 'R':
                ci->expr_R = av_strdup(optarg);
                ci->eval_colors = 1;
                break;
            case 'G':
                ci->expr_G = av_strdup(optarg);
                ci->eval_colors = 1;
                break;
            case 'B':
                ci->expr_B = av_strdup(optarg);
                ci->eval_colors = 1;
                break;
            case 'A':
                ci->expr_A = av_strdup(optarg);
                break;
            case 'C':
                rgbtxt = optarg;
                break;
            case 'c':
                color = optarg;
                break;
            case 'F':
                font = optarg;
                break;
            case 't':
                ci->text = av_strdup(optarg);
                break;
            case 'f':
                ci->file = av_strdup(optarg);
                break;
            case 'x':
                ci->expr_x = av_strdup(optarg);
                break;
            case 'y':
                ci->expr_y = av_strdup(optarg);
                break;
            case 'i':
                ci->fileImage = av_strdup(optarg);
                break;
            case '?':
                fprintf(stderr, "Unrecognized argument '%s'\n", argv[optind]);
                return -1;
        }
    }

    if (ci->eval_colors && !(ci->expr_R && ci->expr_G && ci->expr_B))
    {
        fprintf(stderr, "You must specify expressions for all or no colors.\n");
        return -1;
    }

    if (ci->text || ci->file) {
        ci->fn = imlib_load_font(font);
        if (!ci->fn) {
            fprintf(stderr, "Failed to load font '%s'\n", font);
            return -1;
        }
        imlib_context_set_font(ci->fn);
        imlib_context_set_direction(IMLIB_TEXT_TO_RIGHT);
    }

    if (color) {
        char buff[256];
        int done = 0;

        if (ci->eval_colors)
        {
            fprintf(stderr, "You must not specify both a color name and expressions for the colors.\n");
            return -1;
        }