commit 5d8a00d3a799201db060ed9a8db638ab2923ed48
author Julio Barba <juliobbv@gmail.com> Fri Sep 19 18:51:59 2025 -0400
committer Wan-Teh Chang <wtc@google.com> Tue Sep 23 08:37:02 2025 -0700
tree c428a3002ec5cb59e22a3d80b7f2c4d41c841f61
parent 4c28bc878f0bd6e3f0609ae049923ebd3e82f0bd

Fix aom_hadamard_4x4_c() comments

The dynamic range stated by the comments was wrong, so this commit
fixes them to match the actual implementation.

Also, mention that the function is good for HBD usage, as this is
what's already happening inside highbd_wht_fwd_txfm().

Change-Id: Iaf7bc0101f4020221ee12d6181cc311cd7ad9b60

aom_dsp/avg.c

diff --git a/aom_dsp/avg.c b/aom_dsp/avg.c
index 5cba8a8..6cfbfdd 100644
--- a/aom_dsp/avg.c
+++ b/aom_dsp/avg.c
@@ -119,18 +119,20 @@
   int16_t buffer2[16];
   int16_t *tmp_buf = &buffer[0];
   for (idx = 0; idx < 4; ++idx) {
-    hadamard_col4(src_diff, src_stride, tmp_buf);  // src_diff: 9 bit
-                                                   // dynamic range [-255, 255]
+    // src_diff: 9 bit (8b), 13 bit (HBD)
+    // dynamic range [-255, 255] (8b), [-4095, 4095] (HBD)
+    hadamard_col4(src_diff, src_stride, tmp_buf);
     tmp_buf += 4;
     ++src_diff;
   }
 
   tmp_buf = &buffer[0];
   for (idx = 0; idx < 4; ++idx) {
-    hadamard_col4(tmp_buf, 4, buffer2 + 4 * idx);  // tmp_buf: 12 bit
-    // dynamic range [-2040, 2040]
-    // buffer2: 15 bit
-    // dynamic range [-16320, 16320]
+    // tmp_buf: 10 bit (8b), 14 bit (HBD)
+    // dynamic range [-510, 510] (8b), [-8190, 8190] (HBD)
+    // buffer2: 11 bit (8b), 15 bit (HBD)
+    // dynamic range [-1020, 1020] (8b), [-16380, 16380] (HBD)
+    hadamard_col4(tmp_buf, 4, buffer2 + 4 * idx);
     ++tmp_buf;
   }