[FFmpeg-devel] [PATCH v3 2/4] lavc/libxavs2: optimize data access

[hwrenx at 126.com]

From: hwren <hwrenx at 126.com>

Optimize data access from multiplication to iteration.

Signed-off-by: hwren <hwrenx at 126.com>
---
 libavcodec/libxavs2.c | 45 +++++++++++++++++++++++++++++----------------
 1 file changed, 29 insertions(+), 16 deletions(-)

diff --git a/libavcodec/libxavs2.c b/libavcodec/libxavs2.c
index 0179a1e..b5c07ec 100644
--- a/libavcodec/libxavs2.c
+++ b/libavcodec/libxavs2.c
@@ -132,29 +132,42 @@ static av_cold int xavs2_init(AVCodecContext *avctx)
 
 static void xavs2_copy_frame_with_shift(xavs2_picture_t *pic, const AVFrame *frame, const int shift_in)
 {
-    int j, k;
-    for (k = 0; k < 3; k++) {
-        int i_stride = pic->img.i_stride[k];
-        for (j = 0; j < pic->img.i_lines[k]; j++) {
-            uint16_t *p_plane = (uint16_t *)&pic->img.img_planes[k][j * i_stride];
-            int i;
-            uint8_t *p_buffer = frame->data[k] + frame->linesize[k] * j;
-            memset(p_plane, 0, i_stride);
-            for (i = 0; i < pic->img.i_width[k]; i++) {
-                p_plane[i] = p_buffer[i] << shift_in;
+    uint16_t *p_plane;
+    uint8_t *p_buffer;
+    int wIdx;
+    int hIdx;
+    int plane;
+
+    for (plane = 0; plane < 3; ++plane) {
+        p_plane  = (uint16_t *)pic->img.img_planes[plane];
+        p_buffer = frame->data[plane];
+        for (hIdx = 0; hIdx < pic->img.i_lines[plane]; ++hIdx) {
+            memset(p_plane, 0, pic->img.i_stride[plane]);
+            for (wIdx = 0; wIdx < pic->img.i_width[plane]; ++wIdx) {
+                p_plane[wIdx] = p_buffer[wIdx] << shift_in;
             }
+            p_plane += pic->img.i_stride[plane];
+            p_buffer += frame->linesize[plane];
         }
     }
 }
 
 static void xavs2_copy_frame(xavs2_picture_t *pic, const AVFrame *frame)
 {
-    int j, k;
-    for (k = 0; k < 3; k++) {
-        for (j = 0; j < pic->img.i_lines[k]; j++) {
-            memcpy( pic->img.img_planes[k] + pic->img.i_stride[k] * j,
-                    frame->data[k]+frame->linesize[k] * j,
-                    pic->img.i_width[k] * pic->img.in_sample_size);
+    uint8_t *p_plane;
+    uint8_t *p_buffer;
+    int hIdx;
+    int plane;
+    int stride;
+
+    for (plane = 0; plane < 3; ++plane) {
+        p_plane  = pic->img.img_planes[plane];
+        p_buffer = frame->data[plane];
+        stride = pic->img.i_width[plane] * pic->img.in_sample_size;
+        for (hIdx = 0; hIdx < pic->img.i_lines[plane]; ++hIdx) {
+            memcpy(p_plane, p_buffer, stride);
+            p_plane += pic->img.i_stride[plane];
+            p_buffer += frame->linesize[plane];
         }
     }
 }
-- 
2.7.4