diff --git a/libavcodec/ffv1.c b/libavcodec/ffv1.c
index 3160817cbc331d2083aa33e6067c2954feb3e7cb..6d44df0b3b70fdc8a3389b25e4b6453c79a498d1 100644
--- a/libavcodec/ffv1.c
+++ b/libavcodec/ffv1.c
@@ -1907,6 +1907,8 @@ static int read_header(FFV1Context *f){
         fs->ac= f->ac;
         fs->packed_at_lsb= f->packed_at_lsb;
 
+        fs->slice_damaged = 0;
+
         if(f->version == 2){
             fs->slice_x     = get_symbol(c, state, 0)   *f->width ;
             fs->slice_y     = get_symbol(c, state, 0)   *f->height;
@@ -2026,7 +2028,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac
         }
         buf_p -= v;
 
-        fs->slice_damaged = 0;
         if(f->ec){
             unsigned crc = av_crc(av_crc_get_table(AV_CRC_32_IEEE), 0, buf_p, v);
             if(crc){