IFF: add support for uncompressed ACBM type

src/imageformats/chunks.cpp

@@ -8,6 +8,7 @@
 #include "chunks_p.h"
 #include "packbits_p.h"
 
+#include <QBuffer>
 #include <QDebug>
 #include <QLoggingCategory>
 
@@ -243,7 +244,9 @@ IFFChunk::ChunkList IFFChunk::innerFromDevice(QIODevice *d, bool *ok, IFFChunk *
     for (; !d->atEnd() && (nextChunkPos == 0 || d->pos() < nextChunkPos);) {
         auto cid = d->peek(4);
         QSharedPointer<IFFChunk> chunk;
-        if (cid == ANNO_CHUNK) {
+        if (cid == ABIT_CHUNK) {
+            chunk = QSharedPointer<IFFChunk>(new ABITChunk());
+        } else if (cid == ANNO_CHUNK) {
             chunk = QSharedPointer<IFFChunk>(new ANNOChunk());
         } else if (cid == AUTH_CHUNK) {
             chunk = QSharedPointer<IFFChunk>(new AUTHChunk());
@@ -285,7 +288,7 @@ IFFChunk::ChunkList IFFChunk::innerFromDevice(QIODevice *d, bool *ok, IFFChunk *
             chunk = QSharedPointer<IFFChunk>(new XMP0Chunk());
         } else { // unknown chunk
             chunk = QSharedPointer<IFFChunk>(new IFFChunk());
-            qCInfo(LOG_IFFPLUGIN) << "IFFChunk::innerFromDevice: unknown chunk" << cid;
+            qCDebug(LOG_IFFPLUGIN) << "IFFChunk::innerFromDevice: unknown chunk" << cid;
         }
 
         // change the alignment to the one of main chunk (required for unknown Maya IFF chunks)
@@ -596,7 +599,7 @@ bool BODYChunk::isValid() const
 
 QByteArray BODYChunk::strideRead(QIODevice *d, const BMHDChunk *header, const CAMGChunk *camg, const CMAPChunk *cmap, bool isPbm) const
 {
-    if (!isValid() || header == nullptr) {
+    if (!isValid() || header == nullptr || d == nullptr) {
         return {};
     }
 
@@ -849,6 +852,68 @@ QByteArray BODYChunk::deinterleave(const QByteArray &planes, const BMHDChunk *he
     return ba;
 }
 
+/* ******************
+ * *** ABIT Chunk ***
+ * ****************** */
+
+ABITChunk::~ABITChunk()
+{
+
+}
+
+ABITChunk::ABITChunk() : BODYChunk()
+{
+
+}
+
+bool ABITChunk::isValid() const
+{
+    return chunkId() == ABITChunk::defaultChunkId();
+}
+
+QByteArray ABITChunk::strideRead(QIODevice *d, const BMHDChunk *header, const CAMGChunk *camg, const CMAPChunk *cmap, bool isPbm) const
+{
+    if (!isValid() || header == nullptr || d == nullptr) {
+        return {};
+    }
+    if (header->compression() != BMHDChunk::Compression::Uncompressed || isPbm) {
+        return {};
+    }
+
+    // convert ABIT data to an ILBM line on the fly
+    auto ilbmLine = QByteArray(strideSize(header, isPbm), char());
+    auto rowSize = header->rowLen();
+    auto height = header->height();
+    if (_y >= height) {
+        return {};
+    }
+    for (qint32 plane = 0, planes = qint32(header->bitplanes()); plane < planes; ++plane) {
+        if (!seek(d, qint64(plane) * rowSize * height + _y * rowSize))
+            return {};
+        auto offset = qint64(plane) * rowSize;
+        if (offset + rowSize > ilbmLine.size())
+            return {};
+        if (d->read(ilbmLine.data() + offset, rowSize) != rowSize)
+            return {};
+    }
+    // next line on the next run
+    ++_y;
+
+    // decode the ILBM line
+    QBuffer buf;
+    buf.setData(ilbmLine);
+    if (!buf.open(QBuffer::ReadOnly)) {
+        return {};
+    }
+    return BODYChunk::strideRead(&buf, header, camg, cmap, isPbm);
+}
+
+bool ABITChunk::resetStrideRead(QIODevice *d) const
+{
+    _y = 0;
+    return BODYChunk::resetStrideRead(d);
+}
+
 /* ******************
  * *** FORM Chunk ***
  * ****************** */
@@ -883,6 +948,8 @@ bool FORMChunk::innerReadStructure(QIODevice *d)
         setChunks(IFFChunk::innerFromDevice(d, &ok, this));
     } else if (_type == PBM__FORM_TYPE) {
         setChunks(IFFChunk::innerFromDevice(d, &ok, this));
+    } else if (_type == ACBM_FORM_TYPE) {
+        setChunks(IFFChunk::innerFromDevice(d, &ok, this));
     }
     return ok;
 }

src/imageformats/chunks_p.h

@@ -44,6 +44,7 @@
 #define PRO8_CHUNK QByteArray("PRO8")
 
 // FORM ILBM IFF
+#define ABIT_CHUNK QByteArray("ABIT")
 #define BMHD_CHUNK QByteArray("BMHD")
 #define BODY_CHUNK QByteArray("BODY")
 #define CAMG_CHUNK QByteArray("CAMG")
@@ -70,6 +71,7 @@
 #define VERS_CHUNK QByteArray("VERS")
 #define XMP0_CHUNK QByteArray("XMP0") // https://aminet.net/package/docs/misc/IFF-metadata
 
+#define ACBM_FORM_TYPE QByteArray("ACBM")
 #define ILBM_FORM_TYPE QByteArray("ILBM")
 #define PBM__FORM_TYPE QByteArray("PBM ")
 #define CIMG_FOR4_TYPE QByteArray("CIMG")
@@ -573,20 +575,21 @@ public:
      * \return The scanline as requested for QImage.
      * \warning Call resetStrideRead() once before this one.
      */
-    QByteArray strideRead(QIODevice *d, const BMHDChunk *header, const CAMGChunk *camg = nullptr, const CMAPChunk *cmap = nullptr, bool isPbm = false) const;
+    virtual QByteArray strideRead(QIODevice *d, const BMHDChunk *header, const CAMGChunk *camg = nullptr, const CMAPChunk *cmap = nullptr, bool isPbm = false) const;
 
     /*!
      * \brief resetStrideRead
      * Reset the stride read set the position at the beginning of the data and reset all buffers.
-     * \param d The device
+     * \param d The device.
      * \param header The BMHDChunk chunk (mandatory)
      * \param camg The CAMG chunk (optional)
      * \return True on success, otherwise false.
      * \sa strideRead
+     * \note Must be called once before strideRead().
      */
-    bool resetStrideRead(QIODevice *d) const;
+    virtual bool resetStrideRead(QIODevice *d) const;
 
-private:
+protected:
     /*!
      * \brief strideSize
      * \param isPbm Set true if the image is PBM.
@@ -596,9 +599,35 @@ private:
 
     QByteArray deinterleave(const QByteArray &planes, const BMHDChunk *header, const CAMGChunk *camg = nullptr, const CMAPChunk *cmap = nullptr, bool isPbm = false) const;
 
+private:
     mutable QByteArray _readBuffer;
 };
 
+
+/*!
+ * \brief The ABITChunk class
+ */
+class ABITChunk : public BODYChunk
+{
+public:
+    virtual ~ABITChunk() override;
+    ABITChunk();
+    ABITChunk(const ABITChunk& other) = default;
+    ABITChunk& operator =(const ABITChunk& other) = default;
+
+    virtual bool isValid() const override;
+
+    CHUNKID_DEFINE(ABIT_CHUNK)
+
+    virtual QByteArray strideRead(QIODevice *d, const BMHDChunk *header, const CAMGChunk *camg = nullptr, const CMAPChunk *cmap = nullptr, bool isPbm = false) const override;
+
+    virtual bool resetStrideRead(QIODevice *d) const override;
+
+private:
+    mutable qint32 _y;
+};
+
+
 /*!
  * \brief The FORMChunk class
  */

src/imageformats/iff.cpp

@@ -91,6 +91,17 @@ bool IFFHandler::canRead(QIODevice *device)
         return false;
     }
 
+    // I avoid parsing obviously incorrect files
+    auto cid = device->peek(4);
+    if (cid != CAT__CHUNK &&
+        cid != FORM_CHUNK &&
+        cid != LIST_CHUNK &&
+        cid != CAT4_CHUNK &&
+        cid != FOR4_CHUNK &&
+        cid != LIS4_CHUNK) {
+        return false;
+    }
+
     auto ok = false;
     auto pos = device->pos();
     auto chunks = IFFChunk::fromDevice(device, &ok);
@@ -220,6 +231,11 @@ bool IFFHandler::readStandardImage(QImage *image)
     }
 
     auto bodies = IFFChunk::searchT<BODYChunk>(form);
+    if (bodies.isEmpty()) {
+        auto abits = IFFChunk::searchT<ABITChunk>(form);
+        for (auto &&abit : abits)
+            bodies.append(abit);
+    }
     if (bodies.isEmpty()) {
         img.fill(0);
     } else {