IMAGE: Add support for Indeo4 transparency plane

This is used by TITANIC for most of the furniture in the SGT
stateroom and Titania's parts.

2 files changed, 16 insertions, 11 deletions

diff --git a/image/codecs/indeo/indeo.cpp b/image/codecs/indeo/indeo.cpp
index f420069139..6b6e3557fe 100644
--- a/image/codecs/indeo/indeo.cpp
+++ b/image/codecs/indeo/indeo.cpp
@@ -491,6 +491,8 @@ IndeoDecoderBase::~IndeoDecoderBase() {
 	IVIPlaneDesc::freeBuffers(_ctx._planes);
 	if (_ctx._mbVlc._custTab._table)
 		_ctx._mbVlc._custTab.freeVlc();
+	if (_ctx._transVlc._custTab._table)
+		_ctx._transVlc._custTab.freeVlc();
 
 	delete _ctx._pFrame;
 }
@@ -575,11 +577,23 @@ int IndeoDecoderBase::decodeIndeoFrame() {
 	outputPlane(&_ctx._planes[2], frame->_data[1], frame->_linesize[1]);
 	outputPlane(&_ctx._planes[1], frame->_data[2], frame->_linesize[2]);
 
+	// Merge the planes into the final surface
+	Graphics::Surface s = _surface->getSubArea(Common::Rect(0, 0, _surface->w, _surface->h));
+	YUVToRGBMan.convert410(&s, Graphics::YUVToRGBManager::kScaleITU,
+		frame->_data[0], frame->_data[1], frame->_data[2], frame->_width, frame->_height,
+		frame->_width, frame->_width);
+
+	if (_ctx._hasTransp)
+		decodeTransparency();
+
 	// If the bidirectional mode is enabled, next I and the following P
 	// frame will be sent together. Unfortunately the approach below seems
 	// to be the only way to handle the B-frames mode.
 	// That's exactly the same Intel decoders do.
 	if (_ctx._isIndeo4 && _ctx._frameType == IVI4_FRAMETYPE_INTRA) {
+		// TODO: It appears from the reference decoder that this should be
+		// aligning GetBits to a 32-bit boundary before reading again?
+
 		int left;
 
 		// skip version string
@@ -595,19 +609,9 @@ int IndeoDecoderBase::decodeIndeoFrame() {
 		}
 	}
 
-	// Merge the planes into the final surface
-	Graphics::Surface s = _surface->getSubArea(Common::Rect(0, 0, _surface->w, _surface->h));
-	YUVToRGBMan.convert410(&s, Graphics::YUVToRGBManager::kScaleITU,
-		frame->_data[0], frame->_data[1], frame->_data[2], frame->_width, frame->_height,
-		frame->_width, frame->_width);
-
 	// Free the now un-needed frame data
 	frame->freeFrame();
 
-	// If there's any transparency data, decode it
-	if (_ctx._hasTransp)
-		decodeTransparency();
-
 	return 0;
 }
 
diff --git a/image/codecs/indeo/indeo.h b/image/codecs/indeo/indeo.h
index dcb7330318..962d06817d 100644
--- a/image/codecs/indeo/indeo.h
+++ b/image/codecs/indeo/indeo.h
@@ -398,6 +398,7 @@ public:
 
 	IVIHuffTab		_mbVlc;			///< current macroblock table descriptor
 	IVIHuffTab		_blkVlc;		///< current block table descriptor
+	IVIHuffTab		_transVlc;		///< current transparency table descriptor
 
 	uint8			_rvmapSel;
 	bool			_inImf;
@@ -566,7 +567,7 @@ protected:
 	/**
 	 * Decodes optional transparency data within Indeo frames
 	 */
-	virtual void decodeTransparency() {}
+	virtual int decodeTransparency() { return -1; }
 
 	/**
 	 * Decodes the Indeo frame from the bit reader already