bilinear.c

xawtv绝版源码

/* 
 * Simple xawtv deinterlacing plugin - bilinear interpolation
 * 
 * CAVEATS: Effectively halves framerate, (working on it)
 * May cause some general slowness (uses more cpu) but the framerate is smooth
 * on my athlon 700, running the -mjc branch of 2.4 kernel (preempt and other
 * patches for desktop performance)
 * Text (in console games for example) looks really ugly
 * 
 * BENEFITS: It's no longer interlaced ;)
 * Looks a metric shitton better than line doubling
 * 
 * AUTHORS:
 * Conrad Kreyling <[e-mail]>
 * Patrick Barrett <[e-mail]>
 * 
 * This is licenced under the GNU GPL until someone tells me I'm stealing code
 * and can't do that ;) www.gnu.org for any version of the license.
 *
 * Based on xawtv-3.66/libng/plugins/flt-nop.c (also GPL)
 */


#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>

#include "grab-ng.h"

static void inline
deinterlace (struct ng_video_buf *frame)
{
  unsigned int x, y;

  for (y = 1; y < frame->fmt.height - 1; y += 2)
    for (x = 0; x < frame->fmt.bytesperline + 1; x++)
      (frame->data[y * (frame->fmt.bytesperline) + x]) =
	((frame->data[((y - 1) * (frame->fmt.bytesperline)) + x]) +
	 (frame->data[((y + 1) * (frame->fmt.bytesperline)) + x])) >> 1;

}


static void *
init (struct ng_video_fmt *out)
{
  /* don't have to carry around status info */
  static int dummy;
  return &dummy;
}

static struct ng_video_buf *
frame (void *handle, struct ng_video_buf *frame)
{
  deinterlace (frame);		// In hindsight, we may not have needed the function ;)
  // Added clarity when we make it more complicated.
  return frame;
}

static void
fini (void *handle)
{
  /* nothing to clean up */
}

/* ------------------------------------------------------------------- */

static struct ng_filter filter = {
  name:"bilinear deinterlace",
  fmts:
    (1 << VIDEO_GRAY)   |
    (1 << VIDEO_RGB15_NATIVE) |
    (1 << VIDEO_RGB16_NATIVE) |
    (1 << VIDEO_BGR24)  |
    (1 << VIDEO_RGB24)  |
    (1 << VIDEO_BGR32)  |
    (1 << VIDEO_RGB32)  |
    (1 << VIDEO_YUYV)   |
    (1 << VIDEO_UYVY),
  init:init,
  frame:frame,
  fini:fini,
};

extern void ng_plugin_init (void);
void
ng_plugin_init (void)
{
  ng_filter_register (NG_PLUGIN_MAGIC,__FILE__,&filter);
}