Fix black borders on Huawei devices when rendering alpha video. (#471)

Co-authored-by: fusionxu <fusionxu@tencent.com>

src/platform/android/GPUDecoder.cpp

@@ -83,7 +83,7 @@ GPUDecoder::~GPUDecoder() {
 }
 
 bool GPUDecoder::initDecoder(JNIEnv* env, const VideoFormat& format) {
-  videoSurface = VideoSurface::Make(format.width, format.height);
+  videoSurface = VideoSurface::Make(format.width, format.height, format.hasAlpha);
   if (videoSurface == nullptr) {
     return false;
   }

src/platform/android/VideoSurface.cpp

@@ -43,8 +43,8 @@ void VideoSurface::InitJNI(JNIEnv* env, const std::string& className) {
   VideoSurface_release = env->GetMethodID(VideoSurfaceClass.get(), "release", "()V");
 }
 
-OESTexture::OESTexture(const tgfx::GLSampler& glSampler, int width, int height)
-    : GLTexture(width, height, tgfx::ImageOrigin::TopLeft) {
+OESTexture::OESTexture(const tgfx::GLSampler& glSampler, int width, int height, bool hasAlpha)
+    : GLTexture(width, height, tgfx::ImageOrigin::TopLeft), hasAlpha(hasAlpha) {
   sampler = glSampler;
 }
 
@@ -55,7 +55,7 @@ void OESTexture::setTextureSize(int width, int height) {
 }
 
 void OESTexture::computeTransform() {
-  if (textureWidth == 0 || textureHeight == 0) {
+  if (textureWidth == 0 || textureHeight == 0 || hasAlpha) {
     return;
   }
   // https://cs.android.com/android/platform/superproject/+/master:frameworks/native/libs/nativedisplay/surfacetexture/SurfaceTexture.cpp;l=275;drc=master;bpv=0;bpt=1
@@ -79,6 +79,10 @@ void OESTexture::computeTransform() {
 }
 
 tgfx::Point OESTexture::getTextureCoord(float x, float y) const {
+  if (hasAlpha) {
+    // 如果有 alpha 通道，不需要缩小纹素，解决华为设备上的黑边问题
+    return {x / static_cast<float>(textureWidth), y / static_cast<float>(textureHeight)};
+  }
   return {x / static_cast<float>(width()) * sx + tx, y / static_cast<float>(height()) * sy + ty};
 }
 
@@ -89,7 +93,7 @@ void OESTexture::onReleaseGPU() {
   }
 }
 
-std::shared_ptr<VideoSurface> VideoSurface::Make(int width, int height) {
+std::shared_ptr<VideoSurface> VideoSurface::Make(int width, int height, bool hasAlpha) {
   auto env = JNIEnvironment::Current();
   if (env == nullptr) {
     return nullptr;
@@ -99,11 +103,12 @@ std::shared_ptr<VideoSurface> VideoSurface::Make(int width, int height) {
   if (surface.empty()) {
     return nullptr;
   }
-  return std::shared_ptr<VideoSurface>(new VideoSurface(env, surface.get(), width, height));
+  return std::shared_ptr<VideoSurface>(
+      new VideoSurface(env, surface.get(), width, height, hasAlpha));
 }
 
-VideoSurface::VideoSurface(JNIEnv* env, jobject surface, int width, int height)
-    : width(width), height(height) {
+VideoSurface::VideoSurface(JNIEnv* env, jobject surface, int width, int height, bool hasAlpha)
+    : width(width), height(height), hasAlpha(hasAlpha) {
   videoSurface.reset(env, surface);
 }
 
@@ -145,7 +150,7 @@ std::shared_ptr<tgfx::Texture> VideoSurface::makeTexture(tgfx::Context* context)
   if (oesTexture == nullptr) {
     auto textureWidth = env->CallIntMethod(videoSurface.get(), VideoSurface_videoWidth);
     auto textureHeight = env->CallIntMethod(videoSurface.get(), VideoSurface_videoHeight);
-    oesTexture = tgfx::Resource::Wrap(context, new OESTexture(glInfo, width, height));
+    oesTexture = tgfx::Resource::Wrap(context, new OESTexture(glInfo, width, height, hasAlpha));
     oesTexture->setTextureSize(textureWidth, textureHeight);
     oesTexture->attachedSurface.reset(env, videoSurface.get());
   }

src/platform/android/VideoSurface.h

@@ -24,7 +24,7 @@
 namespace pag {
 class OESTexture : public tgfx::GLTexture {
  public:
-  OESTexture(const tgfx::GLSampler& sampler, int width, int height);
+  OESTexture(const tgfx::GLSampler& sampler, int width, int height, bool hasAlpha);
 
   tgfx::Point getTextureCoord(float x, float y) const override;
 
@@ -37,6 +37,7 @@ class OESTexture : public tgfx::GLTexture {
 
   int textureWidth = 0;
   int textureHeight = 0;
+  bool hasAlpha = false;
   // 持有 Java 的 Surface，确保即使 GPUDecoder 提前释放也能正常被使用。
   Global<jobject> attachedSurface;
   float sx = 1.0f;
@@ -51,7 +52,7 @@ class VideoSurface {
  public:
   static void InitJNI(JNIEnv* env, const std::string& className);
 
-  static std::shared_ptr<VideoSurface> Make(int width, int height);
+  static std::shared_ptr<VideoSurface> Make(int width, int height, bool hasAlpha = false);
 
   ~VideoSurface();
 
@@ -67,12 +68,13 @@ class VideoSurface {
   Global<jobject> videoSurface;
   int width = 0;
   int height = 0;
+  bool hasAlpha = false;
   uint32_t deviceID = 0;
   tgfx::GLSampler glInfo = {};
   std::shared_ptr<OESTexture> oesTexture = nullptr;
   mutable std::atomic_bool hasPendingTextureImage = {false};
 
-  VideoSurface(JNIEnv* env, jobject surface, int width, int height);
+  VideoSurface(JNIEnv* env, jobject surface, int width, int height, bool hasAlpha);
   bool attachToContext(JNIEnv* env, tgfx::Context* context);
   bool updateTexImage(JNIEnv* env);
 };

src/rendering/sequences/VideoSequenceDemuxer.cpp

@@ -24,6 +24,7 @@ VideoSequenceDemuxer::VideoSequenceDemuxer(std::shared_ptr<File> file, VideoSequ
     : file(std::move(file)), sequence(sequence) {
   format.width = sequence->getVideoWidth();
   format.height = sequence->getVideoHeight();
+  format.hasAlpha = sequence->alphaStartX + sequence->alphaStartY > 0;
   for (auto& header : sequence->headers) {
     auto bytes = tgfx::Data::MakeWithoutCopy(header->data(), header->length());
     format.headers.push_back(std::move(bytes));

src/rendering/video/VideoFormat.h

@@ -30,6 +30,7 @@ struct VideoFormat {
   tgfx::YUVColorRange colorRange = tgfx::YUVColorRange::MPEG;
   int width = 0;
   int height = 0;
+  bool hasAlpha = false;
   int64_t duration = 0;
   float frameRate = 0.0;
   int maxReorderSize = 4;