From 4b6194e15e318ef6db70029866a5a8eca79e93bd Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Sat, 15 Jan 2022 12:17:31 -0600
Subject: [PATCH] Add chroma location buffer attachment

---
 app/streaming/video/ffmpeg-renderers/vt.mm | 41 ++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/app/streaming/video/ffmpeg-renderers/vt.mm b/app/streaming/video/ffmpeg-renderers/vt.mm
index f5b05c14..25ac131f 100644
--- a/app/streaming/video/ffmpeg-renderers/vt.mm
+++ b/app/streaming/video/ffmpeg-renderers/vt.mm
@@ -186,6 +186,47 @@ public:
                               kCVImageBufferChromaSubsampling_420,
                               kCVAttachmentMode_ShouldPropagate);
 
+        switch (frame->chroma_location) {
+        case AVCHROMA_LOC_LEFT:
+            CVBufferSetAttachment(pixBuf,
+                                  kCVImageBufferChromaLocationTopFieldKey,
+                                  kCVImageBufferChromaLocation_Left,
+                                  kCVAttachmentMode_ShouldPropagate);
+            break;
+        case AVCHROMA_LOC_CENTER:
+            CVBufferSetAttachment(pixBuf,
+                                  kCVImageBufferChromaLocationTopFieldKey,
+                                  kCVImageBufferChromaLocation_Center,
+                                  kCVAttachmentMode_ShouldPropagate);
+            break;
+        case AVCHROMA_LOC_TOPLEFT:
+            CVBufferSetAttachment(pixBuf,
+                                  kCVImageBufferChromaLocationTopFieldKey,
+                                  kCVImageBufferChromaLocation_TopLeft,
+                                  kCVAttachmentMode_ShouldPropagate);
+            break;
+        case AVCHROMA_LOC_TOP:
+            CVBufferSetAttachment(pixBuf,
+                                  kCVImageBufferChromaLocationTopFieldKey,
+                                  kCVImageBufferChromaLocation_Top,
+                                  kCVAttachmentMode_ShouldPropagate);
+            break;
+        case AVCHROMA_LOC_BOTTOMLEFT:
+            CVBufferSetAttachment(pixBuf,
+                                  kCVImageBufferChromaLocationTopFieldKey,
+                                  kCVImageBufferChromaLocation_BottomLeft,
+                                  kCVAttachmentMode_ShouldPropagate);
+            break;
+        case AVCHROMA_LOC_BOTTOM:
+            CVBufferSetAttachment(pixBuf,
+                                  kCVImageBufferChromaLocationTopFieldKey,
+                                  kCVImageBufferChromaLocation_Bottom,
+                                  kCVAttachmentMode_ShouldPropagate);
+            break;
+        default:
+            break;
+        }
+
         switch (frame->color_primaries) {
         case AVCOL_PRI_BT709:
             CVBufferSetAttachment(pixBuf,