From: Michael Froman <mfroman@mozilla.com>
Date: Thu, 20 Aug 2026 15:17:00 +0000
Subject: Bug 1996020 - Add I420Buffer::CreateOrNull and use it in
 VideoCaptureImpl::IncomingFrame. r=bwc

Differential Revision: https://phabricator.services.mozilla.com/D318847
Mercurial Revision: https://hg.mozilla.org/mozilla-central/rev/f0c6e846e0d33294378079b83208d1a91c5bf293
---
 api/video/i420_buffer.cc                    | 27 ++++++++++++++++++---
 api/video/i420_buffer.h                     | 15 +++++++++++-
 modules/video_capture/video_capture_impl.cc | 11 ++++++++-
 3 files changed, 47 insertions(+), 6 deletions(-)

diff --git a/api/video/i420_buffer.cc b/api/video/i420_buffer.cc
index e9320ced2a..4eec83cd3a 100644
--- a/api/video/i420_buffer.cc
+++ b/api/video/i420_buffer.cc
@@ -54,15 +54,18 @@ I420Buffer::I420Buffer(int width,
                        int height,
                        int stride_y,
                        int stride_u,
-                       int stride_v)
+                       int stride_v,
+                       uint8_t* data)
     : width_(width),
       height_(height),
       stride_y_(stride_y),
       stride_u_(stride_u),
       stride_v_(stride_v),
-      data_(static_cast<uint8_t*>(AlignedMalloc(
-          I420DataSize(width, height, stride_y, stride_u, stride_v),
-          kBufferAlignment))) {
+      data_(data ? data
+                 : static_cast<uint8_t*>(AlignedMalloc(
+                       I420DataSize(width, height, stride_y, stride_u,
+                                    stride_v),
+                       kBufferAlignment))) {
   RTC_DCHECK_GE(stride_u, (width + 1) / 2);
   RTC_DCHECK_GE(stride_v, (width + 1) / 2);
 }
@@ -84,6 +87,22 @@ scoped_refptr<I420Buffer> I420Buffer::Create(int width,
                                       stride_v);
 }
 
+// static
+scoped_refptr<I420Buffer> I420Buffer::CreateOrNull(int width,
+                                                   int height,
+                                                   int stride_y,
+                                                   int stride_u,
+                                                   int stride_v) {
+  uint8_t* data = AlignedMallocOrNull<uint8_t>(
+      I420DataSize(width, height, stride_y, stride_u, stride_v),
+      kBufferAlignment);
+  if (!data) {
+    return nullptr;
+  }
+  return make_ref_counted<I420Buffer>(width, height, stride_y, stride_u,
+                                      stride_v, data);
+}
+
 // static
 scoped_refptr<I420Buffer> I420Buffer::Copy(const I420BufferInterface& source) {
   return Copy(source.width(), source.height(), source.DataY(), source.StrideY(),
diff --git a/api/video/i420_buffer.h b/api/video/i420_buffer.h
index a7a0fb014d..e4935b430c 100644
--- a/api/video/i420_buffer.h
+++ b/api/video/i420_buffer.h
@@ -32,6 +32,11 @@ class RTC_EXPORT I420Buffer : public I420BufferInterface {
                                           int stride_y,
                                           int stride_u,
                                           int stride_v);
+  static scoped_refptr<I420Buffer> CreateOrNull(int width,
+                                                int height,
+                                                int stride_y,
+                                                int stride_u,
+                                                int stride_v);
 
   // Create a new buffer and copy the pixel data.
   static scoped_refptr<I420Buffer> Copy(const I420BufferInterface& buffer);
@@ -100,7 +105,15 @@ class RTC_EXPORT I420Buffer : public I420BufferInterface {
 
  protected:
   I420Buffer(int width, int height);
-  I420Buffer(int width, int height, int stride_y, int stride_u, int stride_v);
+  // If `data` is non-null, it must have been allocated with AlignedMalloc and
+  // be large enough to hold the planes described by the strides; the buffer
+  // takes ownership of it. Otherwise the data is allocated by the constructor.
+  I420Buffer(int width,
+             int height,
+             int stride_y,
+             int stride_u,
+             int stride_v,
+             uint8_t* data = nullptr);
 
   ~I420Buffer() override;
 
diff --git a/modules/video_capture/video_capture_impl.cc b/modules/video_capture/video_capture_impl.cc
index ed83ab6e57..7bf88028ef 100644
--- a/modules/video_capture/video_capture_impl.cc
+++ b/modules/video_capture/video_capture_impl.cc
@@ -200,8 +200,17 @@ int32_t VideoCaptureImpl::IncomingFrame(uint8_t* videoFrame,
   // Setting absolute height (in case it was negative).
   // In Windows, the image starts bottom left, instead of top left.
   // Setting a negative source height, inverts the image (within LibYuv).
-  scoped_refptr<I420Buffer> buffer = I420Buffer::Create(
+  scoped_refptr<I420Buffer> buffer = I420Buffer::CreateOrNull(
       target_width, target_height, stride_y, stride_uv, stride_uv);
+  if (!buffer) {
+    RTC_LOG(LS_ERROR) << "Unable to allocate I420Buffer"
+                      << " (w: " << target_width
+                      << ", h: " << target_height
+                      << ", stride_y: " << stride_y
+                      << ", stride_u: " << stride_uv
+                      << ", stride_v: " << stride_uv << ")";
+    return -1;
+  }
 
   libyuv::RotationMode rotation_mode = libyuv::kRotate0;
   if (apply_rotation_) {