Consider aspect ratio when writing tiff dpi.

TIFFTAG_YRESOLUTION gets now adjusted to sample_aspect_ratio.

libavcodec/tiffenc.c

@@ -436,6 +436,13 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     add_entry1(s, TIFF_ROWSPERSTRIP, TIFF_LONG,     s->rps);
     add_entry(s,  TIFF_STRIP_SIZE,   TIFF_LONG,     strips, s->strip_sizes);
     add_entry(s,  TIFF_XRES,         TIFF_RATIONAL, 1,      res);
+    if (avctx->sample_aspect_ratio.num > 0 &&
+        avctx->sample_aspect_ratio.den > 0) {
+        AVRational y = av_mul_q(av_make_q(s->dpi, 1),
+                                avctx->sample_aspect_ratio);
+        res[0] = y.num;
+        res[1] = y.den;
+    }
     add_entry(s,  TIFF_YRES,         TIFF_RATIONAL, 1,      res);
     add_entry1(s, TIFF_RES_UNIT,     TIFF_SHORT,    2);
 

libavcodec/version.h

@@ -30,7 +30,7 @@
 
 #define LIBAVCODEC_VERSION_MAJOR 55
 #define LIBAVCODEC_VERSION_MINOR  57
-#define LIBAVCODEC_VERSION_MICRO 100
+#define LIBAVCODEC_VERSION_MICRO 101
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \