diff --git a/libavcodec/sgienc.c b/libavcodec/sgienc.c
index 28cec8625f..b172835263 100644
--- a/libavcodec/sgienc.c
+++ b/libavcodec/sgienc.c
@@ -170,8 +170,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
                 }
 
                 buf += length;
-                bytestream_put_byte(&buf, 0);
-                bytestream_put_be32(&lengthtab, length + 1);
+                bytestream_put_be32(&lengthtab, length);
                 in_buf -= p->linesize[0];
             }
         }
diff --git a/tests/ref/lavf/sgi b/tests/ref/lavf/sgi
index a43c1f4287..6f45802d86 100644
--- a/tests/ref/lavf/sgi
+++ b/tests/ref/lavf/sgi
@@ -1,3 +1,3 @@
-7054acafd275e51cec28d4518e213081 *./tests/data/images/sgi/02.sgi
+d446e540a7c18da5fd3cc0e9942cd46f *./tests/data/images/sgi/02.sgi
 ./tests/data/images/sgi/%02d.sgi CRC=0x6da01946
-308151 ./tests/data/images/sgi/02.sgi
+307287 ./tests/data/images/sgi/02.sgi
diff --git a/tests/ref/seek/lavf-sgi b/tests/ref/seek/lavf-sgi
index b07132a669..fac6ad9769 100644
--- a/tests/ref/seek/lavf-sgi
+++ b/tests/ref/seek/lavf-sgi
@@ -1,4 +1,4 @@
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:     -1 size:308336
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:     -1 size:307472
 ret:-EINVAL    st:-1 flags:0  ts:-1.000000
 ret:-EINVAL    st:-1 flags:1  ts: 1.894167
 ret:-EINVAL    st: 0 flags:0  ts: 0.800000
@@ -6,7 +6,7 @@ ret:-EINVAL    st: 0 flags:1  ts:-0.320000
 ret:-EINVAL    st:-1 flags:0  ts: 2.576668
 ret:-EINVAL    st:-1 flags:1  ts: 1.470835
 ret: 0         st: 0 flags:0  ts: 0.360000
-ret: 0         st: 0 flags:1 dts: 0.360000 pts: 0.360000 pos:     -1 size:308572
+ret: 0         st: 0 flags:1 dts: 0.360000 pts: 0.360000 pos:     -1 size:307708
 ret:-EINVAL    st: 0 flags:1  ts:-0.760000
 ret:-EINVAL    st:-1 flags:0  ts: 2.153336
 ret:-EINVAL    st:-1 flags:1  ts: 1.047503
@@ -18,7 +18,7 @@ ret:-EINVAL    st: 0 flags:0  ts:-0.480000
 ret:-EINVAL    st: 0 flags:1  ts: 2.400000
 ret:-EINVAL    st:-1 flags:0  ts: 1.306672
 ret: 0         st:-1 flags:1  ts: 0.200839
-ret: 0         st: 0 flags:1 dts: 0.200000 pts: 0.200000 pos:     -1 size:308294
+ret: 0         st: 0 flags:1 dts: 0.200000 pts: 0.200000 pos:     -1 size:307430
 ret:-EINVAL    st: 0 flags:0  ts:-0.920000
 ret:-EINVAL    st: 0 flags:1  ts: 2.000000
 ret:-EINVAL    st:-1 flags:0  ts: 0.883340
@@ -26,5 +26,5 @@ ret:-EINVAL    st:-1 flags:1  ts:-0.222493
 ret:-EINVAL    st: 0 flags:0  ts: 2.680000
 ret:-EINVAL    st: 0 flags:1  ts: 1.560000
 ret: 0         st:-1 flags:0  ts: 0.460008
-ret: 0         st: 0 flags:1 dts: 0.480000 pts: 0.480000 pos:     -1 size:307773
+ret: 0         st: 0 flags:1 dts: 0.480000 pts: 0.480000 pos:     -1 size:306909
 ret:-EINVAL    st:-1 flags:1  ts:-0.645825