commit b551bb3b8913e330dc0eeb08246729317c31e2f9
author Joe Drago <jdrago@netflix.com> Thu Jun 03 15:22:05 2021 -0700
committer Joe Drago <joedrago@gmail.com> Thu Jun 03 18:09:38 2021 -0700
tree ddf1eee5d9683d83ec927e7454c80fbff61406ca
parent d09319b02bff7d5d61041eca7a589c772c1bb492

Refactor imir implementation to match HEIF Draft Amendment 2, which replaces 'axis' with 'mode' and inverts the behavior

src/read.c

diff --git a/src/read.c b/src/read.c
index a37fb80..d363f84 100644
--- a/src/read.c
+++ b/src/read.c
@@ -1553,10 +1553,10 @@
     BEGIN_STREAM(s, raw, rawLen, diag, "Box[imir]");
 
     avifImageMirror * imir = &prop->u.imir;
-    CHECK(avifROStreamRead(&s, &imir->axis, 1)); // unsigned int (7) reserved = 0; unsigned int (1) axis;
-    if ((imir->axis & 0xfe) != 0) {
+    CHECK(avifROStreamRead(&s, &imir->mode, 1)); // unsigned int (7) reserved = 0; unsigned int (1) mode;
+    if ((imir->mode & 0xfe) != 0) {
         // reserved bits must be 0
-        avifDiagnosticsPrintf(diag, "Box[imir] contains nonzero reserved bits [%u]", imir->axis);
+        avifDiagnosticsPrintf(diag, "Box[imir] contains nonzero reserved bits [%u]", imir->mode);
         return AVIF_FALSE;
     }
     return AVIF_TRUE;

src/write.c

diff --git a/src/write.c b/src/write.c
index 1c1d779..6a2474a 100644
--- a/src/write.c
+++ b/src/write.c
@@ -275,8 +275,8 @@
     }
     if (imageMetadata->transformFlags & AVIF_TRANSFORM_IMIR) {
         avifBoxMarker imir = avifRWStreamWriteBox(s, "imir", AVIF_BOX_SIZE_TBD);
-        uint8_t axis = imageMetadata->imir.axis & 0x1;
-        avifRWStreamWrite(s, &axis, 1); // unsigned int (7) reserved = 0; unsigned int (1) axis;
+        uint8_t mode = imageMetadata->imir.mode & 0x1;
+        avifRWStreamWrite(s, &mode, 1); // unsigned int (7) reserved = 0; unsigned int (1) mode;
         avifRWStreamFinishBox(s, imir);
         if (ipma && itemPropertyIndex) {
             ipmaPush(ipma, ++(*itemPropertyIndex), AVIF_TRUE);