diff --git a/libavcodec/pcxenc.c b/libavcodec/pcxenc.c
index 0f8a140fbf..7f710a2c12 100644
--- a/libavcodec/pcxenc.c
+++ b/libavcodec/pcxenc.c
@@ -105,7 +105,7 @@ static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     const uint8_t *buf_end;
     uint8_t *buf;
 
-    int bpp, nplanes, i, y, line_bytes, written, ret, max_pkt_size;
+    int bpp, nplanes, i, y, line_bytes, written, ret, max_pkt_size, sw, sh;
     const uint32_t *pal = NULL;
     uint32_t palette256[256];
     const uint8_t *src;
@@ -158,6 +158,11 @@ static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     buf     = pkt->data;
     buf_end = pkt->data + pkt->size;
 
+    sw = avctx->sample_aspect_ratio.num;
+    sh = avctx->sample_aspect_ratio.den;
+    if (sw > 0xFFFFu || sh > 0xFFFFu)
+        av_reduce(&sw, &sh, sw, sh, 0xFFFFu);
+
     bytestream_put_byte(&buf, 10);                  // manufacturer
     bytestream_put_byte(&buf, 5);                   // version
     bytestream_put_byte(&buf, 1);                   // encoding
@@ -166,8 +171,8 @@ static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     bytestream_put_le16(&buf, 0);                   // y min
     bytestream_put_le16(&buf, avctx->width - 1);    // x max
     bytestream_put_le16(&buf, avctx->height - 1);   // y max
-    bytestream_put_le16(&buf, 0);                   // horizontal DPI
-    bytestream_put_le16(&buf, 0);                   // vertical DPI
+    bytestream_put_le16(&buf, sw);                  // horizontal DPI
+    bytestream_put_le16(&buf, sh);                  // vertical DPI
     for (i = 0; i < 16; i++)
         bytestream_put_be24(&buf, pal ? pal[i] : 0);// palette (<= 16 color only)
     bytestream_put_byte(&buf, 0);                   // reserved