port imlib2 vhook to swscaler

Patch by Victor Paesa %wzrlpy A arsystel P com%
Original thread + testcase:
Date: Sep 13, 2006 11:06 PM
Subject: Re: [Ffmpeg-devel] [PATCH] enable libswscale

Originally committed as revision 6648 to svn://svn.ffmpeg.org/ffmpeg/trunk

vhook/imlib2.c

@@ -46,6 +46,7 @@
  */
 
 #include "framehook.h"
+#include "swscale.h"
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -59,6 +60,8 @@
 #include <X11/Xlib.h>
 #include <Imlib2.h>
 
+static int sws_flags = SWS_BICUBIC;
+
 typedef struct {
     int dummy;
     Imlib_Font fn;
@@ -68,6 +71,11 @@ typedef struct {
     int x;
     int y;
     struct _CachedImage *cache;
+
+    // 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 {
@@ -87,8 +95,11 @@ void Release(void *ctx)
         imlib_free_image();
         av_free(ci->cache);
     }
-    if (ctx)
+    if (ctx) {
+        sws_freeContext(ci->toRGB_convert_ctx);
+        sws_freeContext(ci->fromRGB_convert_ctx);
         av_free(ctx);
+    }
 }
 
 int Configure(void **ctxp, int argc, char *argv[])
@@ -218,15 +229,24 @@ void Process(void *ctx, AVPicture *picture, enum PixelFormat pix_fmt, int width,
     data = imlib_image_get_data();
 
         avpicture_fill(&picture1, (uint8_t *) data, PIX_FMT_RGBA32, width, height);
-    if (pix_fmt != PIX_FMT_RGBA32) {
-        if (img_convert(&picture1, PIX_FMT_RGBA32,
-                        picture, pix_fmt, width, height) < 0) {
-            goto done;
-        }
-    } else {
-        img_copy(&picture1, picture, PIX_FMT_RGBA32, width, height);
+
+    // if we already got a SWS context, let's realloc if is not re-useable
+    ci->toRGB_convert_ctx = sws_getCachedContext(ci->toRGB_convert_ctx,
+                                width, height, pix_fmt,
+                                width, height, PIX_FMT_RGBA32,
+                                sws_flags, NULL, NULL, NULL);
+    if (ci->toRGB_convert_ctx == NULL) {
+        av_log(NULL, AV_LOG_ERROR,
+               "Cannot initialize the toRGB conversion context\n");
+        exit(1);
     }
 
+// img_convert parameters are          2 first destination, then 4 source
+// sws_scale   parameters are context, 4 first source,      then 2 destination
+    sws_scale(ci->toRGB_convert_ctx,
+             picture->data, picture->linesize, 0, height,
+             picture1.data, picture1.linesize);
+
     imlib_image_set_has_alpha(0);
 
     {
@@ -271,15 +291,20 @@ void Process(void *ctx, AVPicture *picture, enum PixelFormat pix_fmt, int width,
         }
     }
 
-    if (pix_fmt != PIX_FMT_RGBA32) {
-        if (img_convert(picture, pix_fmt,
-                        &picture1, PIX_FMT_RGBA32, width, height) < 0) {
-        }
-    } else {
-        img_copy(picture, &picture1, PIX_FMT_RGBA32, width, height);
+    ci->fromRGB_convert_ctx = sws_getCachedContext(ci->fromRGB_convert_ctx,
+                                    width, height, PIX_FMT_RGBA32,
+                                    width, height, pix_fmt,
+                                    sws_flags, NULL, NULL, NULL);
+    if (ci->fromRGB_convert_ctx == NULL) {
+        av_log(NULL, AV_LOG_ERROR,
+               "Cannot initialize the fromRGB conversion context\n");
+        exit(1);
     }
+// img_convert parameters are          2 first destination, then 4 source
+// sws_scale   parameters are context, 4 first source,      then 2 destination
+    sws_scale(ci->fromRGB_convert_ctx,
+             picture1.data, picture1.linesize, 0, height,
+             picture->data, picture->linesize);
 
-done:
-    ;
 }