From: Alexander Strange <astrange@ithinksw.com>
Date: Thu, 14 Jan 2010 01:32:49 +0000 (+0000)
Subject: Implement alpha channel decoding for BGR HuffYUV.
X-Git-Tag: v0.6~1944
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f267d3ac75942bd0fabb38361e00192b8254ba76;p=platform%2Fupstream%2Flibav.git

Implement alpha channel decoding for BGR HuffYUV.

Since BGR24 is decoded as BGR32, fill its alpha channel with 255
using the appropriate predictors.

Originally committed as revision 21211 to svn://svn.ffmpeg.org/ffmpeg/trunk
---

diff --git a/libavcodec/dsputil.c b/libavcodec/dsputil.c
index a2a313a..41a6377 100644
--- a/libavcodec/dsputil.c
+++ b/libavcodec/dsputil.c
@@ -3632,35 +3632,42 @@ static int add_hfyu_left_prediction_c(uint8_t *dst, const uint8_t *src, int w, i
 #define B 3
 #define G 2
 #define R 1
+#define A 0
 #else
 #define B 0
 #define G 1
 #define R 2
+#define A 3
 #endif
-static void add_hfyu_left_prediction_bgr32_c(uint8_t *dst, const uint8_t *src, int w, int *red, int *green, int *blue){
+static void add_hfyu_left_prediction_bgr32_c(uint8_t *dst, const uint8_t *src, int w, int *red, int *green, int *blue, int *alpha){
     int i;
-    int r,g,b;
+    int r,g,b,a;
     r= *red;
     g= *green;
     b= *blue;
+    a= *alpha;
 
     for(i=0; i<w; i++){
         b+= src[4*i+B];
         g+= src[4*i+G];
         r+= src[4*i+R];
+        a+= src[4*i+A];
 
         dst[4*i+B]= b;
         dst[4*i+G]= g;
         dst[4*i+R]= r;
+        dst[4*i+A]= a;
     }
 
     *red= r;
     *green= g;
     *blue= b;
+    *alpha= a;
 }
 #undef B
 #undef G
 #undef R
+#undef A
 
 #define BUTTERFLY2(o1,o2,i1,i2) \
 o1= (i1)+(i2);\
diff --git a/libavcodec/dsputil.h b/libavcodec/dsputil.h
index 7b218ac..1476ae7 100644
--- a/libavcodec/dsputil.h
+++ b/libavcodec/dsputil.h
@@ -350,7 +350,7 @@ typedef struct DSPContext {
     void (*sub_hfyu_median_prediction)(uint8_t *dst, const uint8_t *src1, const uint8_t *src2, int w, int *left, int *left_top);
     void (*add_hfyu_median_prediction)(uint8_t *dst, const uint8_t *top, const uint8_t *diff, int w, int *left, int *left_top);
     int  (*add_hfyu_left_prediction)(uint8_t *dst, const uint8_t *src, int w, int left);
-    void (*add_hfyu_left_prediction_bgr32)(uint8_t *dst, const uint8_t *src, int w, int *red, int *green, int *blue);
+    void (*add_hfyu_left_prediction_bgr32)(uint8_t *dst, const uint8_t *src, int w, int *red, int *green, int *blue, int *alpha);
     /* this might write to dst[w] */
     void (*add_png_paeth_prediction)(uint8_t *dst, uint8_t *src, uint8_t *top, int w, int bpp);
     void (*bswap_buf)(uint32_t *dst, const uint32_t *src, int w);
diff --git a/libavcodec/huffyuv.c b/libavcodec/huffyuv.c
index 4fa6ddf..3b56bb3 100644
--- a/libavcodec/huffyuv.c
+++ b/libavcodec/huffyuv.c
@@ -39,10 +39,12 @@
 #define B 3
 #define G 2
 #define R 1
+#define A 0
 #else
 #define B 0
 #define G 1
 #define R 2
+#define A 3
 #endif
 
 typedef enum Predictor{
@@ -406,7 +408,7 @@ static av_cold void alloc_temp(HYuvContext *s){
             s->temp[i]= av_malloc(s->width + 16);
         }
     }else{
-        s->temp[0]= av_malloc(4*s->width + 16);
+        s->temp[0]= av_mallocz(4*s->width + 16);
     }
 }
 
@@ -836,7 +838,7 @@ static av_always_inline void decode_bgr_1(HYuvContext *s, int count, int decorre
             s->temp[0][4*i+R] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3);
         }
         if(alpha)
-            get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3); //?!
+            s->temp[0][4*i+A] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3);
     }
 }
 
@@ -1116,11 +1118,11 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac
         }
     }else{
         int y;
-        int leftr, leftg, leftb;
+        int leftr, leftg, leftb, lefta;
         const int last_line= (height-1)*p->linesize[0];
 
         if(s->bitstream_bpp==32){
-            skip_bits(&s->gb, 8);
+            lefta= p->data[0][last_line+A]= get_bits(&s->gb, 8);
             leftr= p->data[0][last_line+R]= get_bits(&s->gb, 8);
             leftg= p->data[0][last_line+G]= get_bits(&s->gb, 8);
             leftb= p->data[0][last_line+B]= get_bits(&s->gb, 8);
@@ -1128,6 +1130,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac
             leftr= p->data[0][last_line+R]= get_bits(&s->gb, 8);
             leftg= p->data[0][last_line+G]= get_bits(&s->gb, 8);
             leftb= p->data[0][last_line+B]= get_bits(&s->gb, 8);
+            lefta= p->data[0][last_line+A]= 255;
             skip_bits(&s->gb, 8);
         }
 
@@ -1136,13 +1139,14 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac
             case LEFT:
             case PLANE:
                 decode_bgr_bitstream(s, width-1);
-                s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + last_line+4, s->temp[0], width-1, &leftr, &leftg, &leftb);
+                s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + last_line+4, s->temp[0], width-1, &leftr, &leftg, &leftb, &lefta);
 
                 for(y=s->height-2; y>=0; y--){ //Yes it is stored upside down.
                     decode_bgr_bitstream(s, width);
 
-                    s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + p->linesize[0]*y, s->temp[0], width, &leftr, &leftg, &leftb);
+                    s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + p->linesize[0]*y, s->temp[0], width, &leftr, &leftg, &leftb, &lefta);
                     if(s->predictor == PLANE){
+                        if(s->bitstream_bpp!=32) lefta=0;
                         if((y&s->interlaced)==0 && y<s->height-1-s->interlaced){
                             s->dsp.add_bytes(p->data[0] + p->linesize[0]*y,
                                              p->data[0] + p->linesize[0]*y + fake_ystride, fake_ystride);