From eb8f76023ef8d97fbd00a62506ce1dfb928d8655 Mon Sep 17 00:00:00 2001
From: Brandon W <bwaggone@umich.edu>
Date: Thu, 8 Aug 2024 22:02:07 -0400
Subject: [PATCH] Allow frames that didn't decode to skip.

---
 src/arch/MovieTexture/MovieTexture_FFMpeg.cpp | 35 ++++++++++++++++---
 src/arch/MovieTexture/MovieTexture_FFMpeg.h   |  5 +++
 .../MovieTexture/MovieTexture_Generic.cpp     |  4 +++
 src/arch/MovieTexture/MovieTexture_Generic.h  |  3 ++
 4 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/src/arch/MovieTexture/MovieTexture_FFMpeg.cpp b/src/arch/MovieTexture/MovieTexture_FFMpeg.cpp
index b61d8faf9e..7772442f3e 100644
--- a/src/arch/MovieTexture/MovieTexture_FFMpeg.cpp
+++ b/src/arch/MovieTexture/MovieTexture_FFMpeg.cpp
@@ -223,8 +223,12 @@ bool MovieDecoder_FFMpeg::IsCurrentFrameReady() {
 	}
 
 	std::lock_guard<std::mutex>(m_FrameBuffer[m_iFrameNumber].lock);
+	if (m_FrameBuffer[m_iFrameNumber].skip) {
+		LOG->Info("Frame %i not decoded, skipping...", m_iFrameNumber);
+		return true;
+	}
 	if (!m_FrameBuffer[m_iFrameNumber].decoded) {
-		LOG->Info("Frame %i not decoded, total frames: %i", m_iFrameNumber, m_totalFrames);
+		LOG->Info("Frame %i not decoded and was not skipped, total frames: %i", m_iFrameNumber, m_totalFrames);
 	}
 	return m_FrameBuffer[m_iFrameNumber].decoded;
 }
@@ -344,19 +348,22 @@ int MovieDecoder_FFMpeg::DecodePacketInBuffer() {
 		m_FrameBuffer.back().packet.data = m_FrameBuffer.back().packet.size ? m_FrameBuffer.back().packet.data : nullptr;
 		int len = m_FrameBuffer.back().packet.size;
 		avcodec::avcodec_send_packet(m_pStreamCodec, &m_FrameBuffer.back().packet);
-		int iGotFrame = !avcodec::avcodec_receive_frame(m_pStreamCodec, &m_FrameBuffer.back().frame);
+		int avcodec_return = avcodec::avcodec_receive_frame(m_pStreamCodec, &m_FrameBuffer.back().frame);
 
 		if (len < 0)
 		{
-			LOG->Warn("avcodec_decode_video2: %i", len);
+			LOG->Warn("avcodec_decode_video2 fatal error, packet size negative: %i", len);
 			return -1;
 		}
 
 		m_iCurrentPacketOffset += len;
 
-		if (!iGotFrame)
+		if (avcodec_return != 0)
 		{
-			LOG->Warn("Frame number %i not successfully decoded into buffer.", static_cast<int>(m_FrameBuffer.size() - 1));
+			LOG->Warn(
+				"Frame number %i not successfully decoded into buffer. avcodec_receive_frame status: %i",
+				static_cast<int>(m_FrameBuffer.size() - 1),
+				avcodec_return);
 			continue;
 		}
 
@@ -385,6 +392,13 @@ int MovieDecoder_FFMpeg::DecodePacketInBuffer() {
 		return 1;
 	}
 
+	// This if statement means the packet did not decode correctly. This is not
+	// necessarily fatal for video playback, but out of caution the frame should
+	// be skipped.
+	if (!m_FrameBuffer.back().decoded) {
+		m_FrameBuffer.back().skip = true;
+	}
+
 	return 0; /* packet done */
 }
 
@@ -510,6 +524,17 @@ int MovieDecoder_FFMpeg::DecodePacket( float fTargetTime )
 	return 0; /* packet done */
 }
 
+bool MovieDecoder_FFMpeg::SkipNextFrame() {
+	if (m_iFrameNumber > (m_totalFrames - 1)) {
+		return true;
+	}
+	if (m_FrameBuffer[m_iFrameNumber].skip) {
+		m_iFrameNumber++;
+		return true;
+	}
+	return false;
+}
+
 bool MovieDecoder_FFMpeg::GetFrame(RageSurface* pSurface)
 {
 	avcodec::AVFrame pict;
diff --git a/src/arch/MovieTexture/MovieTexture_FFMpeg.h b/src/arch/MovieTexture/MovieTexture_FFMpeg.h
index e2601a3c96..9d572c6df7 100644
--- a/src/arch/MovieTexture/MovieTexture_FFMpeg.h
+++ b/src/arch/MovieTexture/MovieTexture_FFMpeg.h
@@ -30,6 +30,7 @@ struct FrameHolder {
 	float frameTimestamp;
 	float frameDelay;
 	bool decoded = false;
+	bool skip = false;
 	std::mutex lock; // Protects the frame as it's being initialized.
 
 	FrameHolder() = default;
@@ -42,6 +43,7 @@ struct FrameHolder {
 		frameTimestamp = fh.frameTimestamp;
 		frameDelay = fh.frameDelay;
 		decoded = fh.decoded;
+		skip = fh.skip;
 	}
 };
 
@@ -102,6 +104,9 @@ public:
 
 	void Cancel() { cancel = true; };
 
+	// If the next frame to display had an issue decoding, skip it.
+	bool SkipNextFrame();
+
 private:
 	void Init();
 	RString OpenCodec();
diff --git a/src/arch/MovieTexture/MovieTexture_Generic.cpp b/src/arch/MovieTexture/MovieTexture_Generic.cpp
index eaf300ff6d..80e5cfdab2 100644
--- a/src/arch/MovieTexture/MovieTexture_Generic.cpp
+++ b/src/arch/MovieTexture/MovieTexture_Generic.cpp
@@ -407,6 +407,10 @@ void MovieTexture_Generic::UpdateFrame()
 	/* Just in case we were invalidated: */
 	CreateTexture();
 
+	if (m_pDecoder->SkipNextFrame()) {
+		return;
+	}
+
 	if(m_pTextureLock != nullptr)
 	{
 		std::uintptr_t iHandle = m_pTextureIntermediate != nullptr ? m_pTextureIntermediate->GetTexHandle(): this->GetTexHandle();
diff --git a/src/arch/MovieTexture/MovieTexture_Generic.h b/src/arch/MovieTexture/MovieTexture_Generic.h
index 3dc08d937b..1521b96fb8 100644
--- a/src/arch/MovieTexture/MovieTexture_Generic.h
+++ b/src/arch/MovieTexture/MovieTexture_Generic.h
@@ -54,6 +54,9 @@ public:
 	 */
 	virtual bool GetFrame( RageSurface *pOut ) = 0;
 
+	// Returns true if the frame should be skipped.
+	virtual bool SkipNextFrame() = 0;
+
 	/* Return the dimensions of the image, in pixels (before aspect ratio
 	 * adjustments). */
 	virtual int GetWidth() const  = 0;