diff --git a/libavcodec/ljpegenc.c b/libavcodec/ljpegenc.c
index fad19cbb76..1af4475b75 100644
--- a/libavcodec/ljpegenc.c
+++ b/libavcodec/ljpegenc.c
@@ -239,7 +239,7 @@ static int ljpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     init_put_bits(&pb, pkt->data, pkt->size);
 
     ff_mjpeg_encode_picture_header(avctx, &pb, NULL, &s->scantable,
-                                   s->pred, s->matrix, s->matrix);
+                                   s->pred, s->matrix, s->matrix, 0);
 
     header_bits = put_bits_count(&pb);
 
diff --git a/libavcodec/mjpegenc.c b/libavcodec/mjpegenc.c
index 58b0f2bb37..6ea113afb2 100644
--- a/libavcodec/mjpegenc.c
+++ b/libavcodec/mjpegenc.c
@@ -82,7 +82,8 @@ static void mjpeg_encode_picture_header(MpegEncContext *s)
 {
     ff_mjpeg_encode_picture_header(s->avctx, &s->pb, s->mjpeg_ctx,
                                    &s->intra_scantable, 0,
-                                   s->intra_matrix, s->chroma_intra_matrix);
+                                   s->intra_matrix, s->chroma_intra_matrix,
+                                   s->slice_context_count > 1);
 
     s->esc_pos = put_bytes_count(&s->pb, 0);
     for (int i = 1; i < s->slice_context_count; i++)
@@ -251,7 +252,7 @@ int ff_mjpeg_encode_stuffing(MpegEncContext *s)
 
     ff_mjpeg_escape_FF(pbc, s->esc_pos);
 
-    if ((s->avctx->active_thread_type & FF_THREAD_SLICE) && mb_y < s->mb_height - 1)
+    if (s->slice_context_count > 1 && mb_y < s->mb_height - 1)
         put_marker(pbc, RST0 + (mb_y&7));
     s->esc_pos = put_bytes_count(pbc, 0);
 
@@ -293,11 +294,14 @@ static int alloc_huffman(MpegEncContext *s)
 av_cold int ff_mjpeg_encode_init(MpegEncContext *s)
 {
     MJpegContext *const m = &((MJPEGEncContext*)s)->mjpeg;
-    int ret;
+    int ret, use_slices;
 
     s->mjpeg_ctx = m;
+    use_slices = s->avctx->slices > 0 ? s->avctx->slices > 1 :
+                 (s->avctx->active_thread_type & FF_THREAD_SLICE) &&
+                 s->avctx->thread_count > 1;
 
-    if (s->codec_id == AV_CODEC_ID_AMV || (s->avctx->active_thread_type & FF_THREAD_SLICE))
+    if (s->codec_id == AV_CODEC_ID_AMV || use_slices)
         m->huffman = HUFFMAN_TABLE_DEFAULT;
 
     if (s->mpv_flags & FF_MPV_FLAG_QP_RD) {
diff --git a/libavcodec/mjpegenc_common.c b/libavcodec/mjpegenc_common.c
index 7b82644763..4143a372bb 100644
--- a/libavcodec/mjpegenc_common.c
+++ b/libavcodec/mjpegenc_common.c
@@ -61,7 +61,7 @@ static void jpeg_table_header(AVCodecContext *avctx, PutBitContext *p,
                               ScanTable *intra_scantable,
                               uint16_t luma_intra_matrix[64],
                               uint16_t chroma_intra_matrix[64],
-                              int hsample[3])
+                              int hsample[3], int use_slices)
 {
     int i, j, size;
     uint8_t *ptr;
@@ -92,7 +92,7 @@ static void jpeg_table_header(AVCodecContext *avctx, PutBitContext *p,
         }
     }
 
-    if(avctx->active_thread_type & FF_THREAD_SLICE){
+    if (use_slices) {
         put_marker(p, DRI);
         put_bits(p, 16, 4);
         put_bits(p, 16, (avctx->width-1)/(8*hsample[0]) + 1);
@@ -217,7 +217,8 @@ void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb,
                                     MJpegContext *m,
                                     ScanTable *intra_scantable, int pred,
                                     uint16_t luma_intra_matrix[64],
-                                    uint16_t chroma_intra_matrix[64])
+                                    uint16_t chroma_intra_matrix[64],
+                                    int use_slices)
 {
     const int lossless = !m;
     int hsample[4], vsample[4];
@@ -237,7 +238,8 @@ void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb,
     jpeg_put_comments(avctx, pb);
 
     jpeg_table_header(avctx, pb, m, intra_scantable,
-                      luma_intra_matrix, chroma_intra_matrix, hsample);
+                      luma_intra_matrix, chroma_intra_matrix, hsample,
+                      use_slices);
 
     switch (avctx->codec_id) {
     case AV_CODEC_ID_MJPEG:  put_marker(pb, SOF0 ); break;
diff --git a/libavcodec/mjpegenc_common.h b/libavcodec/mjpegenc_common.h
index ac753bf153..ba7c4f93fa 100644
--- a/libavcodec/mjpegenc_common.h
+++ b/libavcodec/mjpegenc_common.h
@@ -33,7 +33,8 @@ void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb,
                                     struct MJpegContext *m,
                                     ScanTable *intra_scantable, int pred,
                                     uint16_t luma_intra_matrix[64],
-                                    uint16_t chroma_intra_matrix[64]);
+                                    uint16_t chroma_intra_matrix[64],
+                                    int use_slices);
 void ff_mjpeg_encode_picture_trailer(PutBitContext *pb, int header_bits);
 void ff_mjpeg_escape_FF(PutBitContext *pb, int start);
 void ff_mjpeg_build_huffman_codes(uint8_t *huff_size, uint16_t *huff_code,