[FFmpeg-devel] [PATCH 07/14] avcodec/ffv1dec: Don't copy fields unnecessarily

[Andreas Rheinhardt]

Copy slice-only fields only for the slicecontexts and not for the main
contexts in update_thread_context(). The converse is true for e.g.
key_frame_ok which is only used with the main context; when not doing
frame-threaded decoding it is actually only ever set for the main
context, so not setting it for the slice contexts when doing frame
threading is more consistent.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
I wonder whether one should use different structures for the main context
and the slice contexts.

 libavcodec/ffv1dec.c | 27 +++++++++++++--------------
 1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
index ef908a24b7..45bfe21be5 100644
--- a/libavcodec/ffv1dec.c
+++ b/libavcodec/ffv1dec.c
@@ -993,8 +993,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
     return buf_size;
 }
 
-static void copy_fields(FFV1Context *fsdst, const FFV1Context *fssrc,
-                        const FFV1Context *fsrc)
+static void copy_fields(FFV1Context *fsdst, const FFV1Context *fsrc)
 {
     fsdst->version             = fsrc->version;
     fsdst->micro_version       = fsrc->micro_version;
@@ -1007,18 +1006,8 @@ static void copy_fields(FFV1Context *fsdst, const FFV1Context *fssrc,
     fsdst->colorspace          = fsrc->colorspace;
 
     fsdst->ec                  = fsrc->ec;
-    fsdst->intra               = fsrc->intra;
-    fsdst->slice_damaged       = fssrc->slice_damaged;
-    fsdst->key_frame_ok        = fsrc->key_frame_ok;
 
     fsdst->packed_at_lsb       = fsrc->packed_at_lsb;
-    fsdst->slice_count         = fsrc->slice_count;
-    if (fsrc->version<3){
-        fsdst->slice_x             = fssrc->slice_x;
-        fsdst->slice_y             = fssrc->slice_y;
-        fsdst->slice_width         = fssrc->slice_width;
-        fsdst->slice_height        = fssrc->slice_height;
-    }
 }
 
 #if HAVE_THREADS
@@ -1031,8 +1020,11 @@ static int update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
     if (dst == src)
         return 0;
 
-    copy_fields(fdst, fsrc, fsrc);
+    copy_fields(fdst, fsrc);
     fdst->use32bit     = fsrc->use32bit;
+    fdst->intra        = fsrc->intra;
+    fdst->key_frame_ok = fsrc->key_frame_ok;
+    fdst->slice_count  = fsrc->slice_count;
     memcpy(fdst->state_transition, fsrc->state_transition,
            sizeof(fdst->state_transition));
     memcpy(fdst->quant_table, fsrc->quant_table, sizeof(fsrc->quant_table));
@@ -1040,7 +1032,14 @@ static int update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
     for (i = 0; i < fdst->num_h_slices * fdst->num_v_slices; i++) {
         FFV1Context *fssrc = fsrc->slice_context[i];
         FFV1Context *fsdst = fdst->slice_context[i];
-        copy_fields(fsdst, fssrc, fsrc);
+        copy_fields(fsdst, fsrc);
+        fsdst->slice_damaged = fssrc->slice_damaged;
+        if (fsrc->version < 3) {
+            fsdst->slice_x      = fssrc->slice_x;
+            fsdst->slice_y      = fssrc->slice_y;
+            fsdst->slice_width  = fssrc->slice_width;
+            fsdst->slice_height = fssrc->slice_height;
+        }
     }
     av_assert0(!fdst->plane[0].state);
     av_assert0(!fdst->sample_buffer);
-- 
2.27.0