Reorganize ipma writing a bit to make it easier to add new iprops
diff --git a/src/write.c b/src/write.c
index f411f6d..1b878c0 100644
--- a/src/write.c
+++ b/src/write.c
@@ -8,6 +8,18 @@
#include "aom/aom_encoder.h"
#include "aom/aomcx.h"
+#define MAX_ASSOCIATIONS 16
+struct ipmaArray
+{
+ uint8_t associations[MAX_ASSOCIATIONS];
+ uint8_t count;
+};
+static void ipmaPush(struct ipmaArray * ipma, uint8_t assoc)
+{
+ ipma->associations[ipma->count] = assoc;
+ ++ipma->count;
+}
+
static avifBool encodeOBU(avifImage * image, avifBool alphaOnly, avifRawData * outputOBU, int quality);
static avifBool avifImageIsOpaque(avifImage * image);
@@ -174,12 +186,21 @@
avifBoxMarker iprp = avifStreamWriteBox(&s, "iprp", -1, 0);
{
+ uint8_t ipcoIndex = 0;
+ struct ipmaArray ipmaColor;
+ memset(&ipmaColor, 0, sizeof(ipmaColor));
+ struct ipmaArray ipmaAlpha;
+ memset(&ipmaAlpha, 0, sizeof(ipmaAlpha));
+
avifBoxMarker ipco = avifStreamWriteBox(&s, "ipco", -1, 0);
{
avifBoxMarker ispe = avifStreamWriteBox(&s, "ispe", 0, 0);
avifStreamWriteU32(&s, image->width); // unsigned int(32) image_width;
avifStreamWriteU32(&s, image->height); // unsigned int(32) image_height;
avifStreamFinishBox(&s, ispe);
+ ++ipcoIndex;
+ ipmaPush(&ipmaColor, ipcoIndex); // ipma is 1-indexed, doing this afterwards is correct
+ ipmaPush(&ipmaAlpha, ipcoIndex); // Alpha shares the ispe prop
avifBoxMarker pixiC = avifStreamWriteBox(&s, "pixi", 0, 0);
avifStreamWriteU8(&s, 3); // unsigned int (8) num_channels;
@@ -187,12 +208,16 @@
avifStreamWriteU8(&s, image->depth); // unsigned int (8) bits_per_channel;
avifStreamWriteU8(&s, image->depth); // unsigned int (8) bits_per_channel;
avifStreamFinishBox(&s, pixiC);
+ ++ipcoIndex;
+ ipmaPush(&ipmaColor, ipcoIndex);
if (hasAlpha) {
avifBoxMarker pixiA = avifStreamWriteBox(&s, "pixi", 0, 0);
avifStreamWriteU8(&s, 1); // unsigned int (8) num_channels;
avifStreamWriteU8(&s, image->depth); // unsigned int (8) bits_per_channel;
avifStreamFinishBox(&s, pixiA);
+ ++ipcoIndex;
+ ipmaPush(&ipmaAlpha, ipcoIndex);
}
}
avifStreamFinishBox(&s, ipco);
@@ -202,16 +227,18 @@
int ipmaCount = hasAlpha ? 2 : 1;
avifStreamWriteU32(&s, ipmaCount); // unsigned int(32) entry_count;
- avifStreamWriteU16(&s, 1); // unsigned int(16) item_ID;
- avifStreamWriteU8(&s, 2); // unsigned int(8) association_count;
- avifStreamWriteU8(&s, 1); // bit(1) essential; unsigned int(7) property_index;
- avifStreamWriteU8(&s, 2); // bit(1) essential; unsigned int(7) property_index;
+ avifStreamWriteU16(&s, 1); // unsigned int(16) item_ID;
+ avifStreamWriteU8(&s, ipmaColor.count); // unsigned int(8) association_count;
+ for (int i = 0; i < ipmaColor.count; ++i) {
+ avifStreamWriteU8(&s, ipmaColor.associations[i]); // bit(1) essential; unsigned int(7) property_index;
+ }
if (hasAlpha) {
- avifStreamWriteU16(&s, 2); // unsigned int(16) item_ID;
- avifStreamWriteU8(&s, 2); // unsigned int(8) association_count;
- avifStreamWriteU8(&s, 1); // bit(1) essential; unsigned int(7) property_index;
- avifStreamWriteU8(&s, 3); // bit(1) essential; unsigned int(7) property_index;
+ avifStreamWriteU16(&s, 2); // unsigned int(16) item_ID;
+ avifStreamWriteU8(&s, ipmaAlpha.count); // unsigned int(8) association_count;
+ for (int i = 0; i < ipmaAlpha.count; ++i) {
+ avifStreamWriteU8(&s, ipmaAlpha.associations[i]); // bit(1) essential; unsigned int(7) property_index;
+ }
}
}
avifStreamFinishBox(&s, ipma);
