lavc: Edge emulation with dst/src linesize

Allow supporting files for which the image stride is smaller than
the maximum block size + number of subpel mc taps, e.g. a 64x64 VP9
file or a 16x16 VP8 file with -fflags +emu_edge.

1 files changed, 12 insertions, 11 deletions

diff --git a/libavcodec/videodsp_template.c b/libavcodec/videodsp_template.c
index 5d5a32ff60..98313ac5cd 100644
--- a/libavcodec/videodsp_template.c
+++ b/libavcodec/videodsp_template.c
@@ -22,7 +22,8 @@
 #include "bit_depth_template.c"
 
 static void FUNC(ff_emulated_edge_mc)(uint8_t *buf, const uint8_t *src,
-                                      ptrdiff_t linesize,
+                                      ptrdiff_t buf_linesize,
+                                      ptrdiff_t src_linesize,
                                       int block_w, int block_h,
                                       int src_x, int src_y, int w, int h)
 {
@@ -30,10 +31,10 @@ static void FUNC(ff_emulated_edge_mc)(uint8_t *buf, const uint8_t *src,
     int start_y, start_x, end_y, end_x;
 
     if (src_y >= h) {
-        src  += (h - 1 - src_y) * linesize;
+        src  += (h - 1 - src_y) * src_linesize;
         src_y = h - 1;
     } else if (src_y <= -block_h) {
-        src  += (1 - block_h - src_y) * linesize;
+        src  += (1 - block_h - src_y) * src_linesize;
         src_y = 1 - block_h;
     }
     if (src_x >= w) {
@@ -52,30 +53,30 @@ static void FUNC(ff_emulated_edge_mc)(uint8_t *buf, const uint8_t *src,
     assert(start_x < end_x && block_w);
 
     w    = end_x - start_x;
-    src += start_y * linesize + start_x * sizeof(pixel);
+    src += start_y * src_linesize + start_x * sizeof(pixel);
     buf += start_x * sizeof(pixel);
 
     // top
     for (y = 0; y < start_y; y++) {
         memcpy(buf, src, w * sizeof(pixel));
-        buf += linesize;
+        buf += buf_linesize;
     }
 
     // copy existing part
     for (; y < end_y; y++) {
         memcpy(buf, src, w * sizeof(pixel));
-        src += linesize;
-        buf += linesize;
+        src += src_linesize;
+        buf += buf_linesize;
     }
 
     // bottom
-    src -= linesize;
+    src -= src_linesize;
     for (; y < block_h; y++) {
         memcpy(buf, src, w * sizeof(pixel));
-        buf += linesize;
+        buf += buf_linesize;
     }
 
-    buf -= block_h * linesize + start_x * sizeof(pixel);
+    buf -= block_h * buf_linesize + start_x * sizeof(pixel);
     while (block_h--) {
         pixel *bufp = (pixel *) buf;
 
@@ -88,6 +89,6 @@ static void FUNC(ff_emulated_edge_mc)(uint8_t *buf, const uint8_t *src,
         for (x = end_x; x < block_w; x++) {
             bufp[x] = bufp[end_x - 1];
         }
-        buf += linesize;
+        buf += buf_linesize;
     }
 }