Cast sample_fmt (as read from bitstream as a 16-bit value) to int16, so that

negative values, e.g. SAMPLE_FMT_NONE (-1), are read correctly also.

Originally committed as revision 22585 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/ffmdec.c

@@ -354,7 +354,7 @@ static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap)
             codec->sample_rate = get_be32(pb);
             codec->channels = get_le16(pb);
             codec->frame_size = get_le16(pb);
-            codec->sample_fmt = get_le16(pb);
+            codec->sample_fmt = (int16_t) get_le16(pb);
             break;
         default:
             goto fail;