Merge remote-tracking branch 'secondlife/release/2024.06-atlasaurus' into 2024.06-atlasaurus

17 files changed, 360 insertions, 129 deletions

diff --git a/indra/llimage/llimage.cpp b/indra/llimage/llimage.cpp
index da5b531857..ca8a4199e8 100644
--- a/indra/llimage/llimage.cpp
+++ b/indra/llimage/llimage.cpp
@@ -774,7 +774,7 @@ U8* LLImageBase::getData()
 
 bool LLImageBase::isBufferInvalid() const
 {
-    return mBadBufferAllocation || mData == NULL ;
+    return mBadBufferAllocation || mData == NULL;
 }
 
 void LLImageBase::setSize(S32 width, S32 height, S32 ncomponents)
@@ -850,6 +850,8 @@ LLImageRaw::~LLImageRaw()
 // virtual
 U8* LLImageRaw::allocateData(S32 size)
 {
+    LLImageDataLock lock(this);
+
     U8* res = LLImageBase::allocateData(size);
     return res;
 }
@@ -857,12 +859,16 @@ U8* LLImageRaw::allocateData(S32 size)
 // virtual
 U8* LLImageRaw::reallocateData(S32 size)
 {
+    LLImageDataLock lock(this);
+
     U8* res = LLImageBase::reallocateData(size);
     return res;
 }
 
 void LLImageRaw::releaseData()
 {
+    LLImageDataLock lock(this);
+
     LLImageBase::setSize(0, 0, 0);
     LLImageBase::setDataAndSize(nullptr, 0);
 }
@@ -870,11 +876,15 @@ void LLImageRaw::releaseData()
 // virtual
 void LLImageRaw::deleteData()
 {
+    LLImageDataLock lock(this);
+
     LLImageBase::deleteData();
 }
 
 void LLImageRaw::setDataAndSize(U8 *data, S32 width, S32 height, S8 components)
 {
+    LLImageDataLock lock(this);
+
     if(data == getData())
     {
         return ;
@@ -888,6 +898,8 @@ void LLImageRaw::setDataAndSize(U8 *data, S32 width, S32 height, S8 components)
 
 bool LLImageRaw::resize(U16 width, U16 height, S8 components)
 {
+    LLImageDataLock lock(this);
+
     if ((getWidth() == width) && (getHeight() == height) && (getComponents() == components) && !isBufferInvalid())
     {
         return true;
@@ -903,6 +915,8 @@ bool LLImageRaw::resize(U16 width, U16 height, S8 components)
 bool LLImageRaw::setSubImage(U32 x_pos, U32 y_pos, U32 width, U32 height,
                              const U8 *data, U32 stride, bool reverse_y)
 {
+    LLImageDataLock lock(this);
+
     if (!getData())
     {
         return false;
@@ -930,6 +944,9 @@ bool LLImageRaw::setSubImage(U32 x_pos, U32 y_pos, U32 width, U32 height,
 void LLImageRaw::clear(U8 r, U8 g, U8 b, U8 a)
 {
     llassert( getComponents() <= 4 );
+
+    LLImageDataLock lock(this);
+
     // This is fairly bogus, but it'll do for now.
     if (isBufferInvalid())
     {
@@ -970,6 +987,8 @@ void LLImageRaw::clear(U8 r, U8 g, U8 b, U8 a)
 // Reverses the order of the rows in the image
 void LLImageRaw::verticalFlip()
 {
+    LLImageDataLock lock(this);
+
     S32 row_bytes = getWidth() * getComponents();
     llassert(row_bytes > 0);
     std::vector<U8> line_buffer(row_bytes);
@@ -1009,6 +1028,8 @@ bool LLImageRaw::checkHasTransparentPixels()
 
 bool LLImageRaw::optimizeAwayAlpha()
 {
+    LLImageDataLock lock(this);
+
     if (getComponents() == 4)
     {
         U8* data = getData();
@@ -1074,6 +1095,8 @@ bool LLImageRaw::makeAlpha()
 
 void LLImageRaw::expandToPowerOfTwo(S32 max_dim, bool scale_image)
 {
+    LLImageDataLock lock(this);
+
     // Find new sizes
     S32 new_width  = expandDimToPowerOfTwo(getWidth(), max_dim);
     S32 new_height = expandDimToPowerOfTwo(getHeight(), max_dim);
@@ -1083,6 +1106,8 @@ void LLImageRaw::expandToPowerOfTwo(S32 max_dim, bool scale_image)
 
 void LLImageRaw::contractToPowerOfTwo(S32 max_dim, bool scale_image)
 {
+    LLImageDataLock lock(this);
+
     // Find new sizes
     S32 new_width  = contractDimToPowerOfTwo(getWidth(), MIN_IMAGE_SIZE);
     S32 new_height = contractDimToPowerOfTwo(getHeight(), MIN_IMAGE_SIZE);
@@ -1132,6 +1157,8 @@ S32 LLImageRaw::contractDimToPowerOfTwo(S32 curr_dim, S32 min_dim)
 
 void LLImageRaw::biasedScaleToPowerOfTwo(S32 max_dim)
 {
+    LLImageDataLock lock(this);
+
     // Find new sizes
     S32 new_width  = biasedDimToPowerOfTwo(getWidth(),max_dim);
     S32 new_height = biasedDimToPowerOfTwo(getHeight(),max_dim);
@@ -1139,6 +1166,7 @@ void LLImageRaw::biasedScaleToPowerOfTwo(S32 max_dim)
     scale( new_width, new_height );
 }
 
+// static
 // Calculates (U8)(255*(a/255.f)*(b/255.f) + 0.5f).  Thanks, Jim Blinn!
 inline U8 LLImageRaw::fastFractionalMult( U8 a, U8 b )
 {
@@ -1147,10 +1175,13 @@ inline U8 LLImageRaw::fastFractionalMult( U8 a, U8 b )
 }
 
 
-void LLImageRaw::composite( LLImageRaw* src )
+void LLImageRaw::composite( const LLImageRaw* src )
 {
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataSharedLock lockIn(src);
+    LLImageDataLock lockOut(this);
+
     if (!validateSrcAndDst("LLImageRaw::composite", src, dst))
     {
         return;
@@ -1189,12 +1220,14 @@ void LLImageRaw::composite( LLImageRaw* src )
 
 
 // Src and dst can be any size.  Src has 4 components.  Dst has 3 components.
-void LLImageRaw::compositeScaled4onto3(LLImageRaw* src)
+void LLImageRaw::compositeScaled4onto3(const LLImageRaw* src)
 {
     LL_INFOS() << "compositeScaled4onto3" << LL_ENDL;
 
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataLock lock(this);
+
     llassert( (4 == src->getComponents()) && (3 == dst->getComponents()) );
 
     S32 temp_data_size = src->getWidth() * dst->getHeight() * src->getComponents();
@@ -1216,14 +1249,16 @@ void LLImageRaw::compositeScaled4onto3(LLImageRaw* src)
 
 
 // Src and dst are same size.  Src has 4 components.  Dst has 3 components.
-void LLImageRaw::compositeUnscaled4onto3( LLImageRaw* src )
+void LLImageRaw::compositeUnscaled4onto3( const LLImageRaw* src )
 {
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataLock lock(this);
+
     llassert( (3 == src->getComponents()) || (4 == src->getComponents()) );
     llassert( (src->getWidth() == dst->getWidth()) && (src->getHeight() == dst->getHeight()) );
 
-    U8* src_data = src->getData();
+    const U8* src_data = src->getData();
     U8* dst_data = dst->getData();
     S32 pixels = getWidth() * getHeight();
     while( pixels-- )
@@ -1253,10 +1288,13 @@ void LLImageRaw::compositeUnscaled4onto3( LLImageRaw* src )
 }
 
 
-void LLImageRaw::copyUnscaledAlphaMask( LLImageRaw* src, const LLColor4U& fill)
+void LLImageRaw::copyUnscaledAlphaMask( const LLImageRaw* src, const LLColor4U& fill)
 {
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataSharedLock lockIn(src);
+    LLImageDataLock lockOut(this);
+
     if (!validateSrcAndDst("LLImageRaw::copyUnscaledAlphaMask", src, dst))
     {
         return;
@@ -1267,7 +1305,7 @@ void LLImageRaw::copyUnscaledAlphaMask( LLImageRaw* src, const LLColor4U& fill)
     llassert( (src->getWidth() == dst->getWidth()) && (src->getHeight() == dst->getHeight()) );
 
     S32 pixels = getWidth() * getHeight();
-    U8* src_data = src->getData();
+    const U8* src_data = src->getData();
     U8* dst_data = dst->getData();
     for ( S32 i = 0; i < pixels; i++ )
     {
@@ -1284,6 +1322,8 @@ void LLImageRaw::copyUnscaledAlphaMask( LLImageRaw* src, const LLColor4U& fill)
 // Fill the buffer with a constant color
 void LLImageRaw::fill( const LLColor4U& color )
 {
+    LLImageDataLock lock(this);
+
     if (isBufferInvalid())
     {
         LL_WARNS() << "Invalid image buffer" << LL_ENDL;
@@ -1345,16 +1385,21 @@ LLPointer<LLImageRaw> LLImageRaw::duplicate()
         return this; //nobody else refences to this image, no need to duplicate.
     }
 
+    LLImageDataSharedLock lock(this);
+
     //make a duplicate
     LLPointer<LLImageRaw> dup = new LLImageRaw(getData(), getWidth(), getHeight(), getComponents());
     return dup;
 }
 
 // Src and dst can be any size.  Src and dst can each have 3 or 4 components.
-void LLImageRaw::copy(LLImageRaw* src)
+void LLImageRaw::copy(const LLImageRaw* src)
 {
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataSharedLock lockIn(src);
+    LLImageDataLock lockOut(this);
+
     if (!validateSrcAndDst("LLImageRaw::copy", src, dst))
     {
         return;
@@ -1400,10 +1445,12 @@ void LLImageRaw::copy(LLImageRaw* src)
 }
 
 // Src and dst are same size.  Src and dst have same number of components.
-void LLImageRaw::copyUnscaled(LLImageRaw* src)
+void LLImageRaw::copyUnscaled(const LLImageRaw* src)
 {
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataLock lock(this);
+
     llassert( (1 == src->getComponents()) || (3 == src->getComponents()) || (4 == src->getComponents()) );
     llassert( src->getComponents() == dst->getComponents() );
     llassert( (src->getWidth() == dst->getWidth()) && (src->getHeight() == dst->getHeight()) );
@@ -1413,7 +1460,7 @@ void LLImageRaw::copyUnscaled(LLImageRaw* src)
 
 
 // Src and dst can be any size.  Src has 3 components.  Dst has 4 components.
-void LLImageRaw::copyScaled3onto4(LLImageRaw* src)
+void LLImageRaw::copyScaled3onto4(const LLImageRaw* src)
 {
     llassert( (3 == src->getComponents()) && (4 == getComponents()) );
 
@@ -1425,7 +1472,7 @@ void LLImageRaw::copyScaled3onto4(LLImageRaw* src)
 
 
 // Src and dst can be any size.  Src has 4 components.  Dst has 3 components.
-void LLImageRaw::copyScaled4onto3(LLImageRaw* src)
+void LLImageRaw::copyScaled4onto3(const LLImageRaw* src)
 {
     llassert( (4 == src->getComponents()) && (3 == getComponents()) );
 
@@ -1437,15 +1484,17 @@ void LLImageRaw::copyScaled4onto3(LLImageRaw* src)
 
 
 // Src and dst are same size.  Src has 4 components.  Dst has 3 components.
-void LLImageRaw::copyUnscaled4onto3( LLImageRaw* src )
+void LLImageRaw::copyUnscaled4onto3( const LLImageRaw* src )
 {
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataLock lock(this);
+
     llassert( (3 == dst->getComponents()) && (4 == src->getComponents()) );
     llassert( (src->getWidth() == dst->getWidth()) && (src->getHeight() == dst->getHeight()) );
 
     S32 pixels = getWidth() * getHeight();
-    U8* src_data = src->getData();
+    const U8* src_data = src->getData();
     U8* dst_data = dst->getData();
     for( S32 i=0; i<pixels; i++ )
     {
@@ -1459,15 +1508,18 @@ void LLImageRaw::copyUnscaled4onto3( LLImageRaw* src )
 
 
 // Src and dst are same size.  Src has 3 components.  Dst has 4 components.
-void LLImageRaw::copyUnscaled3onto4( LLImageRaw* src )
+void LLImageRaw::copyUnscaled3onto4( const LLImageRaw* src )
 {
     LLImageRaw* dst = this;  // Just for clarity.
+
+    LLImageDataLock lock(this);
+
     llassert( 3 == src->getComponents() );
     llassert( 4 == dst->getComponents() );
     llassert( (src->getWidth() == dst->getWidth()) && (src->getHeight() == dst->getHeight()) );
 
     S32 pixels = getWidth() * getHeight();
-    U8* src_data = src->getData();
+    const U8* src_data = src->getData();
     U8* dst_data = dst->getData();
     for( S32 i=0; i<pixels; i++ )
     {
@@ -1482,10 +1534,13 @@ void LLImageRaw::copyUnscaled3onto4( LLImageRaw* src )
 
 
 // Src and dst can be any size.  Src and dst have same number of components.
-void LLImageRaw::copyScaled( LLImageRaw* src )
+void LLImageRaw::copyScaled( const LLImageRaw* src )
 {
     LLImageRaw* dst = this;  // Just for clarity.
 
+    LLImageDataSharedLock lockIn(src);
+    LLImageDataLock lockOut(this);
+
     if (!validateSrcAndDst("LLImageRaw::copyScaled", src, dst))
     {
         return;
@@ -1527,6 +1582,8 @@ void LLImageRaw::copyScaled( LLImageRaw* src )
 
 bool LLImageRaw::scale( S32 new_width, S32 new_height, bool scale_image_data )
 {
+    LLImageDataLock lock(this);
+
     S32 components = getComponents();
     if (components != 1 && components != 3 && components != 4)
     {
@@ -1613,6 +1670,8 @@ LLPointer<LLImageRaw> LLImageRaw::scaled(S32 new_width, S32 new_height)
 {
     LLPointer<LLImageRaw> result;
 
+    LLImageDataLock lock(this);
+
     S32 components = getComponents();
     if (components != 1 && components != 3 && components != 4)
     {
@@ -1658,7 +1717,7 @@ LLPointer<LLImageRaw> LLImageRaw::scaled(S32 new_width, S32 new_height)
     return result;
 }
 
-void LLImageRaw::copyLineScaled( U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len, S32 in_pixel_step, S32 out_pixel_step )
+void LLImageRaw::copyLineScaled( const U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len, S32 in_pixel_step, S32 out_pixel_step )
 {
     const S32 components = getComponents();
     llassert( components >= 1 && components <= 4 );
@@ -1685,7 +1744,7 @@ void LLImageRaw::copyLineScaled( U8* in, U8* out, S32 in_pixel_len, S32 out_pixe
             S32 t0 = x * out_pixel_step * components;
             S32 t1 = index0 * in_pixel_step * components;
             U8* outp = out + t0;
-            U8* inp = in + t1;
+            const U8* inp = in + t1;
             for (S32 i = 0; i < components; ++i)
             {
                 *outp = *inp;
@@ -1773,7 +1832,7 @@ void LLImageRaw::copyLineScaled( U8* in, U8* out, S32 in_pixel_len, S32 out_pixe
     }
 }
 
-void LLImageRaw::compositeRowScaled4onto3( U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len )
+void LLImageRaw::compositeRowScaled4onto3( const U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len )
 {
     llassert( getComponents() == 3 );
 
@@ -1869,7 +1928,6 @@ void LLImageRaw::compositeRowScaled4onto3( U8* in, U8* out, S32 in_pixel_len, S3
     }
 }
 
-
 void LLImageRaw::addEmissive(LLImageRaw* src)
 {
     LLImageRaw* dst = this;  // Just for clarity.
@@ -1935,9 +1993,11 @@ void LLImageRaw::addEmissiveScaled(LLImageRaw* src)
     dst->addEmissiveUnscaled(&temp);
 }
 
-
-bool LLImageRaw::validateSrcAndDst(std::string func, LLImageRaw* src, LLImageRaw* dst)
+bool LLImageRaw::validateSrcAndDst(std::string func, const LLImageRaw* src, const LLImageRaw* dst)
 {
+    LLImageDataSharedLock lockIn(src);
+    LLImageDataLock lockOut(dst);
+
     if (!src || !dst || src->isBufferInvalid() || dst->isBufferInvalid())
     {
         LL_WARNS() << func << ": Source: ";
@@ -2171,6 +2231,61 @@ LLImageFormatted* LLImageFormatted::createFromType(S8 codec)
 }
 
 // static
+S8 LLImageFormatted::getCodecFromMimeType(std::string_view mimetype)
+{
+    if (mimetype == "image/bmp")
+    {
+        return IMG_CODEC_BMP;
+    }
+    else if (mimetype == "image/tga")
+    {
+        return IMG_CODEC_TGA;
+    }
+    else if (mimetype == "image/jpeg")
+    {
+        return IMG_CODEC_JPEG;
+    }
+    else if (mimetype == "image/png")
+    {
+        return IMG_CODEC_PNG;
+    }
+    else if (mimetype == "image/j2c")
+    {
+        return IMG_CODEC_J2C;
+    }
+    else if (mimetype == "image/dxt")
+    {
+        return IMG_CODEC_DXT;
+    }
+    return IMG_CODEC_INVALID;
+}
+
+// static
+LLImageFormatted* LLImageFormatted::createFromMimeType(std::string_view mimetype)
+{
+    S8 codec = getCodecFromMimeType(mimetype);
+    return createFromType(codec);
+}
+
+// static
+LLImageFormatted* LLImageFormatted::loadFromMemory(const U8* data_in, U32 size, std::string_view mimetype)
+{
+    LLImageFormatted* image = createFromMimeType(mimetype);
+    if (image)
+    {
+        U8* data = image->allocateData(size);
+        memcpy(data, data_in, size);
+
+        if (!image->updateData())
+        {
+            delete image;
+            image = NULL;
+        }
+    }
+    return image;
+}
+
+// static
 LLImageFormatted* LLImageFormatted::createFromExtension(const std::string& instring)
 {
     std::string exten;
@@ -2250,6 +2365,8 @@ bool LLImageFormatted::decodeChannels(LLImageRaw* raw_image,F32  decode_time, S3
 // virtual
 U8* LLImageFormatted::allocateData(S32 size)
 {
+    LLImageDataLock lock(this);
+
     U8* res = LLImageBase::allocateData(size); // calls deleteData()
     sGlobalFormattedMemory += getDataSize();
     return res;
@@ -2258,6 +2375,8 @@ U8* LLImageFormatted::allocateData(S32 size)
 // virtual
 U8* LLImageFormatted::reallocateData(S32 size)
 {
+    LLImageDataLock lock(this);
+
     sGlobalFormattedMemory -= getDataSize();
     U8* res = LLImageBase::reallocateData(size);
     sGlobalFormattedMemory += getDataSize();
@@ -2267,6 +2386,12 @@ U8* LLImageFormatted::reallocateData(S32 size)
 // virtual
 void LLImageFormatted::deleteData()
 {
+    LLImageDataLock lock(this);
+
+    if (mDecoding)
+    {
+        LL_ERRS() << "LLImageFormatted::deleteData() is called during decoding" << LL_ENDL;
+    }
     sGlobalFormattedMemory -= getDataSize();
     LLImageBase::deleteData();
 }
@@ -2292,6 +2417,8 @@ void LLImageFormatted::sanityCheck()
 
 bool LLImageFormatted::copyData(U8 *data, S32 size)
 {
+    LLImageDataLock lock(this);
+
     if ( data && ((data != getData()) || (size != getDataSize())) )
     {
         deleteData();
@@ -2304,6 +2431,8 @@ bool LLImageFormatted::copyData(U8 *data, S32 size)
 // LLImageFormatted becomes the owner of data
 void LLImageFormatted::setData(U8 *data, S32 size)
 {
+    LLImageDataLock lock(this);
+
     if (data && data != getData())
     {
         deleteData();
@@ -2317,6 +2446,8 @@ void LLImageFormatted::appendData(U8 *data, S32 size)
 {
     if (data)
     {
+        LLImageDataLock lock(this);
+
         if (!getData())
         {
             setData(data, size);
@@ -2334,6 +2465,7 @@ void LLImageFormatted::appendData(U8 *data, S32 size)
 
 //----------------------------------------------------------------------------
 
+
 bool LLImageFormatted::load(const std::string &filename, int load_size)
 {
     resetLastError();
@@ -2358,6 +2490,9 @@ bool LLImageFormatted::load(const std::string &filename, int load_size)
     {
         load_size = file_size;
     }
+
+    LLImageDataLock lock(this);
+
     bool res;
     U8 *data = allocateData(load_size);
     if (data)
@@ -2396,6 +2531,8 @@ bool LLImageFormatted::save(const std::string &filename)
         return false;
     }
 
+    LLImageDataSharedLock lock(this);
+
     S32 result = outfile.write(getData(), getDataSize());
     outfile.close() ;
     return (result != 0);
diff --git a/indra/llimage/llimage.h b/indra/llimage/llimage.h
index 9b16711b85..42eecbb97c 100644
--- a/indra/llimage/llimage.h
+++ b/indra/llimage/llimage.h
@@ -117,6 +117,10 @@ class LLImageBase
 protected:
     virtual ~LLImageBase();
 
+    virtual void deleteData();
+    virtual U8* allocateData(S32 size = -1);
+    virtual U8* reallocateData(S32 size = -1);
+
 public:
     LLImageBase();
 
@@ -126,10 +130,6 @@ public:
         TYPE_AVATAR_BAKE = 1,
     };
 
-    virtual void deleteData();
-    virtual U8* allocateData(S32 size = -1);
-    virtual U8* reallocateData(S32 size = -1);
-
     virtual void dump();
     virtual void sanityCheck();
 
@@ -171,10 +171,27 @@ private:
 
     S8 mComponents;
 
-    bool mBadBufferAllocation ;
-    bool mAllowOverSize ;
+    bool mBadBufferAllocation;
+    bool mAllowOverSize;
+
+private:
+    mutable LLSharedMutex mDataMutex;
+
+public:
+    template<bool SHARED>
+    class DataLock : LLSharedMutexLockTemplate<SHARED>
+    {
+    public:
+        DataLock(const LLImageBase* image)
+        : LLSharedMutexLockTemplate<SHARED>(image ? &image->mDataMutex : nullptr)
+        {
+        }
+    };
 };
 
+using LLImageDataLock = LLImageBase::DataLock<false>;
+using LLImageDataSharedLock = LLImageBase::DataLock<true>;
+
 // Raw representation of an image (used for textures, and other uncompressed formats
 class LLImageRaw : public LLImageBase
 {
@@ -238,42 +255,30 @@ public:
     LLPointer<LLImageRaw> duplicate();
 
     // Src and dst can be any size.  Src and dst can each have 3 or 4 components.
-    void copy( LLImageRaw* src );
+    void copy( const LLImageRaw* src );
 
     // Src and dst are same size.  Src and dst have same number of components.
-    void copyUnscaled( LLImageRaw* src );
+    void copyUnscaled( const LLImageRaw* src );
 
     // Src and dst are same size.  Src has 4 components.  Dst has 3 components.
-    void copyUnscaled4onto3( LLImageRaw* src );
+    void copyUnscaled4onto3( const LLImageRaw* src );
 
     // Src and dst are same size.  Src has 3 components.  Dst has 4 components.
-    void copyUnscaled3onto4( LLImageRaw* src );
+    void copyUnscaled3onto4( const LLImageRaw* src );
 
     // Src and dst are same size.  Src has 1 component.  Dst has 4 components.
     // Alpha component is set to source alpha mask component.
     // RGB components are set to fill color.
-    void copyUnscaledAlphaMask( LLImageRaw* src, const LLColor4U& fill);
+    void copyUnscaledAlphaMask( const LLImageRaw* src, const LLColor4U& fill);
 
     // Src and dst can be any size.  Src and dst have same number of components.
-    void copyScaled( LLImageRaw* src );
-
-    // Src and dst can be any size.  Src has 3 components.  Dst has 4 components.
-    void copyScaled3onto4( LLImageRaw* src );
-
-    // Src and dst can be any size.  Src has 4 components.  Dst has 3 components.
-    void copyScaled4onto3( LLImageRaw* src );
+    void copyScaled( const LLImageRaw* src );
 
 
     // Composite operations
 
     // Src and dst can be any size.  Src and dst can each have 3 or 4 components.
-    void composite( LLImageRaw* src );
-
-    // Src and dst can be any size.  Src has 4 components.  Dst has 3 components.
-    void compositeScaled4onto3( LLImageRaw* src );
-
-    // Src and dst are same size.  Src has 4 components.  Dst has 3 components.
-    void compositeUnscaled4onto3( LLImageRaw* src );
+    void composite( const LLImageRaw* src );
 
     // Emissive operations used by minimap
     // Roughly emulates GLTF emissive texture, but is not GLTF-compliant
@@ -282,13 +287,25 @@ public:
     void addEmissiveScaled(LLImageRaw* src);
     void addEmissiveUnscaled(LLImageRaw* src);
 protected:
+    // Src and dst can be any size.  Src has 4 components.  Dst has 3 components.
+    void compositeScaled4onto3( const LLImageRaw* src );
+
+    // Src and dst are same size.  Src has 4 components.  Dst has 3 components.
+    void compositeUnscaled4onto3( const LLImageRaw* src );
+
+    // Src and dst can be any size.  Src has 3 components.  Dst has 4 components.
+    void copyScaled3onto4( const LLImageRaw* src );
+
+    // Src and dst can be any size.  Src has 4 components.  Dst has 3 components.
+    void copyScaled4onto3( const LLImageRaw* src );
+
     // Create an image from a local file (generally used in tools)
     //bool createFromFile(const std::string& filename, bool j2c_lowest_mip_only = false);
 
-    void copyLineScaled( U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len, S32 in_pixel_step, S32 out_pixel_step );
-    void compositeRowScaled4onto3( U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len );
+    void copyLineScaled( const U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len, S32 in_pixel_step, S32 out_pixel_step );
+    void compositeRowScaled4onto3( const U8* in, U8* out, S32 in_pixel_len, S32 out_pixel_len );
 
-    U8  fastFractionalMult(U8 a,U8 b);
+    static U8 fastFractionalMult(U8 a, U8 b);
 
     void setDataAndSize(U8 *data, S32 width, S32 height, S8 components) ;
 
@@ -296,7 +313,7 @@ public:
     static S32 sRawImageCount;
 
 private:
-    bool validateSrcAndDst(std::string func, LLImageRaw* src, LLImageRaw* dst);
+    static bool validateSrcAndDst(std::string func, const LLImageRaw* src, const LLImageRaw* dst);
 };
 
 // Compressed representation of image.
@@ -305,7 +322,10 @@ class LLImageFormatted : public LLImageBase
 {
 public:
     static LLImageFormatted* createFromType(S8 codec);
+    static LLImageFormatted* loadFromMemory(const U8* data, U32 size, std::string_view mimetype);
     static LLImageFormatted* createFromExtension(const std::string& instring);
+    static LLImageFormatted* createFromMimeType(std::string_view mimetype);
+    static S8 getCodecFromMimeType(std::string_view mimetype);
 
 protected:
     /*virtual*/ ~LLImageFormatted();
diff --git a/indra/llimage/llimagebmp.cpp b/indra/llimage/llimagebmp.cpp
index 08fcdf39da..2a328675c2 100644
--- a/indra/llimage/llimagebmp.cpp
+++ b/indra/llimage/llimagebmp.cpp
@@ -96,6 +96,8 @@ bool LLImageBMP::updateData()
 {
     resetLastError();
 
+    LLImageDataLock lock(this);
+
     // Check to make sure that this instance has been initialized with data
     U8* mdata = getData();
     if (!mdata || (0 == getDataSize()))
@@ -337,8 +339,11 @@ bool LLImageBMP::decode(LLImageRaw* raw_image, F32 decode_time)
 
     resetLastError();
 
+    LLImageDataLock lockIn(this);
+    LLImageDataLock lockOut(raw_image);
+
     // Check to make sure that this instance has been initialized with data
-    U8* mdata = getData();
+    const U8* mdata = getData();
     if (!mdata || (0 == getDataSize()))
     {
         setLastError("llimagebmp trying to decode an image with no data!");
@@ -351,7 +356,7 @@ bool LLImageBMP::decode(LLImageRaw* raw_image, F32 decode_time)
         return false;
     }
 
-    U8* src = mdata + mBitmapOffset;
+    const U8* src = mdata + mBitmapOffset;
     U8* dst = raw_image->getData();
 
     bool success = false;
@@ -398,7 +403,7 @@ U32 LLImageBMP::countTrailingZeros( U32 m )
 }
 
 
-bool LLImageBMP::decodeColorMask16( U8* dst, U8* src )
+bool LLImageBMP::decodeColorMask16( U8* dst, const U8* src )
 {
     llassert( 16 == mBitsPerPixel );
 
@@ -434,7 +439,7 @@ bool LLImageBMP::decodeColorMask16( U8* dst, U8* src )
     return true;
 }
 
-bool LLImageBMP::decodeColorMask32( U8* dst, U8* src )
+bool LLImageBMP::decodeColorMask32( U8* dst, const U8* src )
 {
     // Note: alpha is not supported
 
@@ -478,7 +483,7 @@ bool LLImageBMP::decodeColorMask32( U8* dst, U8* src )
 }
 
 
-bool LLImageBMP::decodeColorTable8( U8* dst, U8* src )
+bool LLImageBMP::decodeColorTable8( U8* dst, const U8* src )
 {
     llassert( (8 == mBitsPerPixel) && (mColorPaletteColors >= 256) );
 
@@ -508,7 +513,7 @@ bool LLImageBMP::decodeColorTable8( U8* dst, U8* src )
 }
 
 
-bool LLImageBMP::decodeTruecolor24( U8* dst, U8* src )
+bool LLImageBMP::decodeTruecolor24( U8* dst, const U8* src )
 {
     llassert( 24 == mBitsPerPixel );
     llassert( 3 == getComponents() );
@@ -542,6 +547,9 @@ bool LLImageBMP::encode(const LLImageRaw* raw_image, F32 encode_time)
 
     resetLastError();
 
+    LLImageDataSharedLock lockIn(raw_image);
+    LLImageDataLock lockOut(this);
+
     S32 src_components = raw_image->getComponents();
     S32 dst_components =  ( src_components < 3 ) ? 1 : 3;
 
diff --git a/indra/llimage/llimagebmp.h b/indra/llimage/llimagebmp.h
index d2cbad1a49..237c3e8d53 100644
--- a/indra/llimage/llimagebmp.h
+++ b/indra/llimage/llimagebmp.h
@@ -45,10 +45,10 @@ public:
     /*virtual*/ bool encode(const LLImageRaw* raw_image, F32 encode_time);
 
 protected:
-    bool        decodeColorTable8( U8* dst, U8* src );
-    bool        decodeColorMask16( U8* dst, U8* src );
-    bool        decodeTruecolor24( U8* dst, U8* src );
-    bool        decodeColorMask32( U8* dst, U8* src );
+    bool        decodeColorTable8( U8* dst, const U8* src );
+    bool        decodeColorMask16( U8* dst, const U8* src );
+    bool        decodeTruecolor24( U8* dst, const U8* src );
+    bool        decodeColorMask32( U8* dst, const U8* src );
 
     U32         countTrailingZeros( U32 m );
 
diff --git a/indra/llimage/llimagedimensionsinfo.cpp b/indra/llimage/llimagedimensionsinfo.cpp
index 997406bb7b..d4efbcfad2 100644
--- a/indra/llimage/llimagedimensionsinfo.cpp
+++ b/indra/llimage/llimagedimensionsinfo.cpp
@@ -201,7 +201,7 @@ bool LLImageDimensionsInfo::getImageDimensionsJpeg()
 
     jpeg_create_decompress  (&cinfo);
     jpeg_stdio_src      (&cinfo, fp);
-    jpeg_read_header    (&cinfo, TRUE);
+    jpeg_read_header    (&cinfo, true);
     cinfo.out_color_space = JCS_RGB;
     jpeg_start_decompress   (&cinfo);
 
diff --git a/indra/llimage/llimagedxt.cpp b/indra/llimage/llimagedxt.cpp
index f75b1a72df..6b960f9077 100644
--- a/indra/llimage/llimagedxt.cpp
+++ b/indra/llimage/llimagedxt.cpp
@@ -176,6 +176,8 @@ bool LLImageDXT::updateData()
 {
     resetLastError();
 
+    LLImageDataLock lock(this);
+
     U8* data = getData();
     S32 data_size = getDataSize();
 
@@ -269,6 +271,9 @@ bool LLImageDXT::decode(LLImageRaw* raw_image, F32 time)
         return false;
     }
 
+    LLImageDataSharedLock lockIn(this);
+    LLImageDataLock lockOut(raw_image);
+
     S32 width = getWidth(), height = getHeight();
     S32 ncomponents = getComponents();
     U8* data = NULL;
@@ -309,6 +314,9 @@ bool LLImageDXT::getMipData(LLPointer<LLImageRaw>& raw, S32 discard)
     {
         LL_ERRS() << "Request for invalid discard level" << LL_ENDL;
     }
+
+    LLImageDataSharedLock lock(this);
+
     U8* data = getData() + getMipOffset(discard);
     S32 width = 0;
     S32 height = 0;
@@ -339,6 +347,8 @@ bool LLImageDXT::encodeDXT(const LLImageRaw* raw_image, F32 time, bool explicit_
         return 0;
     }
 
+    LLImageDataLock lock(this);
+
     S32 width = raw_image->getWidth();
     S32 height = raw_image->getHeight();
 
@@ -430,6 +440,9 @@ bool LLImageDXT::convertToDXR()
         return false;
     }
     mFileFormat = newformat;
+
+    LLImageDataLock lock(this);
+
     S32 width = getWidth(), height = getHeight();
     S32 nmips = calcNumMips(width,height);
     S32 total_bytes = getDataSize();
@@ -463,7 +476,7 @@ bool LLImageDXT::convertToDXR()
 // virtual
 S32 LLImageDXT::calcHeaderSize()
 {
-    return llmax(sizeof(dxtfile_header_old_t), sizeof(dxtfile_header_t));
+    return static_cast<S32>(llmax(sizeof(dxtfile_header_old_t), sizeof(dxtfile_header_t)));
 }
 
 // virtual
diff --git a/indra/llimage/llimagefilter.cpp b/indra/llimage/llimagefilter.cpp
index 1b7835a6ff..0d15906afd 100644
--- a/indra/llimage/llimagefilter.cpp
+++ b/indra/llimage/llimagefilter.cpp
@@ -88,6 +88,8 @@ void LLImageFilter::executeFilter(LLPointer<LLImageRaw> raw_image)
 {
     mImage = raw_image;
 
+    LLImageDataLock lock(mImage);
+
     //std::cout << "Filter : size = " << mFilterData.size() << std::endl;
     for (S32 i = 0; i < mFilterData.size(); ++i)
     {
@@ -779,9 +781,9 @@ void LLImageFilter::filterLinearize(F32 tail, const LLColor3& alpha)
 
     // Compute min and max counts minus tail
     tail = llclampf(tail);
-    S32 total = cumulated_histo[255];
-    S32 min_c = (S32)((F32)(total) * tail);
-    S32 max_c = (S32)((F32)(total) * (1.0 - tail));
+    U32 total = cumulated_histo[255];
+    U32 min_c = (U32)((F32)(total) * tail);
+    U32 max_c = (U32)((F32)(total) * (1.0 - tail));
 
     // Find min and max values
     S32 min_v = 0;
@@ -796,9 +798,9 @@ void LLImageFilter::filterLinearize(F32 tail, const LLColor3& alpha)
     }
 
     // Compute linear lookup table
-    U8 linear_red_lut[256];
-    U8 linear_green_lut[256];
-    U8 linear_blue_lut[256];
+    U8 linear_red_lut[256]{};
+    U8 linear_green_lut[256]{};
+    U8 linear_blue_lut[256]{};
     if (max_v == min_v)
     {
         // Degenerated binary split case
@@ -848,16 +850,16 @@ void LLImageFilter::filterEqualize(S32 nb_classes, const LLColor3& alpha)
     }
 
     // Compute deltas
-    S32 total = cumulated_histo[255];
-    S32 delta_count = total / nb_classes;
-    S32 current_count = delta_count;
-    S32 delta_value = 256 / (nb_classes - 1);
-    S32 current_value = 0;
+    U32 total = cumulated_histo[255];
+    U32 delta_count = total / nb_classes;
+    U32 current_count = delta_count;
+    U32 delta_value = 256 / (nb_classes - 1);
+    U32 current_value = 0;
 
     // Compute equalized lookup table
-    U8 equalize_red_lut[256];
-    U8 equalize_green_lut[256];
-    U8 equalize_blue_lut[256];
+    U8 equalize_red_lut[256]{};
+    U8 equalize_green_lut[256]{};
+    U8 equalize_blue_lut[256]{};
     for (S32 i = 0; i < 256; i++)
     {
         // Blend in current_value with alpha values
diff --git a/indra/llimage/llimagej2c.cpp b/indra/llimage/llimagej2c.cpp
index 5175849ad8..0058b91b0f 100644
--- a/indra/llimage/llimagej2c.cpp
+++ b/indra/llimage/llimagej2c.cpp
@@ -107,6 +107,8 @@ bool LLImageJ2C::updateData()
     bool res = true;
     resetLastError();
 
+    LLImageDataLock lock(this);
+
     // Check to make sure that this instance has been initialized with data
     if (!getData() || (getDataSize() < 16))
     {
@@ -157,22 +159,25 @@ bool LLImageJ2C::decodeChannels(LLImageRaw *raw_imagep, F32 decode_time, S32 fir
     LL_PROFILE_ZONE_SCOPED_CATEGORY_TEXTURE;
     LLTimer elapsed;
 
-    bool res = true;
-
     resetLastError();
 
-    // Check to make sure that this instance has been initialized with data
-    if (!getData() || (getDataSize() < 16))
+    bool res;
     {
-        setLastError("LLImageJ2C uninitialized");
-        res = true; // done
-    }
-    else
-    {
-        // Update the raw discard level
-        updateRawDiscardLevel();
+        LLImageDataLock lock(this);
+
         mDecoding = true;
-        res = mImpl->decodeImpl(*this, *raw_imagep, decode_time, first_channel, max_channel_count);
+        // Check to make sure that this instance has been initialized with data
+        if (!getData() || (getDataSize() < 16))
+        {
+            setLastError("LLImageJ2C uninitialized");
+            res = true; // done
+        }
+        else
+        {
+            // Update the raw discard level
+            updateRawDiscardLevel();
+            res = mImpl->decodeImpl(*this, *raw_imagep, decode_time, first_channel, max_channel_count);
+        }
     }
 
     if (res)
@@ -181,12 +186,21 @@ bool LLImageJ2C::decodeChannels(LLImageRaw *raw_imagep, F32 decode_time, S32 fir
         {
             // Failed
             raw_imagep->deleteData();
+            res = false;
         }
         else
         {
             mDecoding = false;
         }
     }
+    else
+    {
+        if (mDecoding)
+        {
+            LL_WARNS() << "decodeImpl failed but mDecoding is true" << LL_ENDL;
+            mDecoding = false;
+        }
+    }
 
     if (!mLastError.empty())
     {
@@ -406,9 +420,10 @@ bool LLImageJ2C::loadAndValidate(const std::string &filename)
 
 bool LLImageJ2C::validate(U8 *data, U32 file_size)
 {
-
     resetLastError();
 
+    LLImageDataLock lock(this);
+
     setData(data, file_size);
 
     bool res = updateData();
diff --git a/indra/llimage/llimagejpeg.cpp b/indra/llimage/llimagejpeg.cpp
index 93f1d0cdc4..0e7ec365d4 100644
--- a/indra/llimage/llimagejpeg.cpp
+++ b/indra/llimage/llimagejpeg.cpp
@@ -50,6 +50,8 @@ bool LLImageJPEG::updateData()
 {
     resetLastError();
 
+    LLImageDataLock lock(this);
+
     // Check to make sure that this instance has been initialized with data
     if (!getData() || (0 == getDataSize()))
     {
@@ -189,6 +191,9 @@ bool LLImageJPEG::decode(LLImageRaw* raw_image, F32 decode_time)
 
     resetLastError();
 
+    LLImageDataLock lockIn(this);
+    LLImageDataLock lockOut(raw_image);
+
     // Check to make sure that this instance has been initialized with data
     if (!getData() || (0 == getDataSize()))
     {
@@ -408,6 +413,8 @@ void LLImageJPEG::encodeTermDestination( j_compress_ptr cinfo )
 {
     LLImageJPEG* self = (LLImageJPEG*) cinfo->client_data;
 
+    LLImageDataLock lock(self);
+
     S32 file_bytes = (S32)(self->mOutputBufferSize - cinfo->dest->free_in_buffer);
     self->allocateData(file_bytes);
 
@@ -484,6 +491,9 @@ bool LLImageJPEG::encode( const LLImageRaw* raw_image, F32 encode_time )
 
     resetLastError();
 
+    LLImageDataSharedLock lockIn(raw_image);
+    LLImageDataLock lockOut(this);
+
     switch( raw_image->getComponents() )
     {
     case 1:
diff --git a/indra/llimage/llimagejpeg.h b/indra/llimage/llimagejpeg.h
index 12249ad8c3..add6657117 100644
--- a/indra/llimage/llimagejpeg.h
+++ b/indra/llimage/llimagejpeg.h
@@ -73,8 +73,6 @@ public:
     static void     errorEmitMessage(j_common_ptr cinfo, int msg_level);
     static void     errorOutputMessage(j_common_ptr cinfo);
 
-    static bool     decompress(LLImageJPEG* imagep);
-
 protected:
     U8*             mOutputBuffer;      // temp buffer used during encoding
     S32             mOutputBufferSize;  // bytes in mOuputBuffer
diff --git a/indra/llimage/llimagepng.cpp b/indra/llimage/llimagepng.cpp
index 4d081ce169..d75084cf08 100644
--- a/indra/llimage/llimagepng.cpp
+++ b/indra/llimage/llimagepng.cpp
@@ -54,6 +54,8 @@ bool LLImagePNG::updateData()
 
     try
     {
+        LLImageDataLock lock(this);
+
         // Check to make sure that this instance has been initialized with data
         if (!getData() || (0 == getDataSize()))
         {
@@ -103,6 +105,9 @@ bool LLImagePNG::decode(LLImageRaw* raw_image, F32 decode_time)
 
     resetLastError();
 
+    LLImageDataSharedLock lockIn(this);
+    LLImageDataLock lockOut(raw_image);
+
     // Check to make sure that this instance has been initialized with data
     if (!getData() || (0 == getDataSize()))
     {
@@ -135,6 +140,9 @@ bool LLImagePNG::encode(const LLImageRaw* raw_image, F32 encode_time)
 
     resetLastError();
 
+    LLImageDataSharedLock lockIn(raw_image);
+    LLImageDataLock lockOut(this);
+
     // Image logical size
     setSize(raw_image->getWidth(), raw_image->getHeight(), raw_image->getComponents());
 
diff --git a/indra/llimage/llimagetga.cpp b/indra/llimage/llimagetga.cpp
index adc98cd81d..25232b77aa 100644
--- a/indra/llimage/llimagetga.cpp
+++ b/indra/llimage/llimagetga.cpp
@@ -108,6 +108,8 @@ bool LLImageTGA::updateData()
 {
     resetLastError();
 
+    LLImageDataLock lock(this);
+
     // Check to make sure that this instance has been initialized with data
     if (!getData() || (0 == getDataSize()))
     {
@@ -328,6 +330,9 @@ bool LLImageTGA::decode(LLImageRaw* raw_image, F32 decode_time)
 {
     llassert_always(raw_image);
 
+    LLImageDataSharedLock lockIn(this);
+    LLImageDataLock lockOut(raw_image);
+
     // Check to make sure that this instance has been initialized with data
     if (!getData() || (0 == getDataSize()))
     {
@@ -462,7 +467,7 @@ bool LLImageTGA::decodeTruecolorNonRle( LLImageRaw* raw_image, bool &alpha_opaqu
 
     S32 pixels = getWidth() * getHeight();
 
-    if (pixels * (mIs15Bit ? 2 : getComponents()) > getDataSize() - mDataOffset)
+    if (pixels * (mIs15Bit ? 2 : getComponents()) > getDataSize() - (S32)mDataOffset)
     { //here we have situation when data size in src less than actually needed
         return false;
     }
@@ -644,6 +649,9 @@ bool LLImageTGA::encode(const LLImageRaw* raw_image, F32 encode_time)
 {
     llassert_always(raw_image);
 
+    LLImageDataSharedLock lockIn(raw_image);
+    LLImageDataLock lockOut(this);
+
     deleteData();
 
     setSize(raw_image->getWidth(), raw_image->getHeight(), raw_image->getComponents());
@@ -1062,6 +1070,9 @@ bool LLImageTGA::decodeAndProcess( LLImageRaw* raw_image, F32 domain, F32 weight
     // --+---Input--------------------------------
     //   |
 
+    LLImageDataSharedLock lockIn(this);
+    LLImageDataLock lockOut(raw_image);
+
     if (!getData() || (0 == getDataSize()))
     {
         setLastError("LLImageTGA trying to decode an image with no data!");
@@ -1168,7 +1179,7 @@ bool LLImageTGA::decodeAndProcess( LLImageRaw* raw_image, F32 domain, F32 weight
 // Reads a .tga file and creates an LLImageTGA with its data.
 bool LLImageTGA::loadFile( const std::string& path )
 {
-    S32 len = path.size();
+    auto len = path.size();
     if( len < 5 )
     {
         return false;
@@ -1195,7 +1206,7 @@ bool LLImageTGA::loadFile( const std::string& path )
     }
 
     U8* buffer = allocateData(file_size);
-    S32 bytes_read = fread(buffer, 1, file_size, file);
+    S32 bytes_read = static_cast<S32>(fread(buffer, 1, file_size, file));
     if( bytes_read != file_size )
     {
         deleteData();
diff --git a/indra/llimage/llimageworker.cpp b/indra/llimage/llimageworker.cpp
index 8ce17b5753..bdaef0c653 100644
--- a/indra/llimage/llimageworker.cpp
+++ b/indra/llimage/llimageworker.cpp
@@ -36,7 +36,7 @@ class ImageRequest
 public:
     ImageRequest(const LLPointer<LLImageFormatted>& image,
                  S32 discard,
-                 BOOL needs_aux,
+                 bool needs_aux,
                  const LLPointer<LLImageDecodeThread::Responder>& responder,
                  U32 request_id);
     virtual ~ImageRequest();
@@ -51,15 +51,14 @@ private:
     LLPointer<LLImageFormatted> mFormattedImage;
     S32 mDiscardLevel;
     U32 mRequestId;
-    BOOL mNeedsAux;
+    bool mNeedsAux;
     // output
     LLPointer<LLImageRaw> mDecodedImageRaw;
     LLPointer<LLImageRaw> mDecodedImageAux;
-    BOOL mDecodedRaw;
-    BOOL mDecodedAux;
+    bool mDecodedRaw;
+    bool mDecodedAux;
     LLPointer<LLImageDecodeThread::Responder> mResponder;
-    std::string mErrorString;
-};
+    std::string mErrorString;};
 
 
 //----------------------------------------------------------------------------
@@ -92,12 +91,15 @@ size_t LLImageDecodeThread::getPending()
 LLImageDecodeThread::handle_t LLImageDecodeThread::decodeImage(
     const LLPointer<LLImageFormatted>& image,
     S32 discard,
-    BOOL needs_aux,
+    bool needs_aux,
     const LLPointer<LLImageDecodeThread::Responder>& responder)
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_TEXTURE;
 
     U32 decode_id = ++mDecodeCount;
+    if (decode_id == 0)
+        decode_id = ++mDecodeCount;
+
     // Instantiate the ImageRequest right in the lambda, why not?
     bool posted = mThreadPool->getQueue().post(
         [req = ImageRequest(image, discard, needs_aux, responder, decode_id)]
@@ -128,14 +130,14 @@ LLImageDecodeThread::Responder::~Responder()
 
 ImageRequest::ImageRequest(const LLPointer<LLImageFormatted>& image,
                            S32 discard,
-                           BOOL needs_aux,
+                           bool needs_aux,
                            const LLPointer<LLImageDecodeThread::Responder>& responder,
                            U32 request_id)
     : mFormattedImage(image),
       mDiscardLevel(discard),
       mNeedsAux(needs_aux),
-      mDecodedRaw(FALSE),
-      mDecodedAux(FALSE),
+      mDecodedRaw(false),
+      mDecodedAux(false),
       mResponder(responder),
       mRequestId(request_id)
 {
@@ -155,10 +157,18 @@ ImageRequest::~ImageRequest()
 bool ImageRequest::processRequest()
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_TEXTURE;
+
+    if (mFormattedImage.isNull())
+        return true;
+
     const F32 decode_time_slice = 0.f; //disable time slicing
     bool done = true;
-    mErrorString.clear();
-    if (!mDecodedRaw && mFormattedImage.notNull())
+
+    LLImageDataLock lockFormatted(mFormattedImage);
+    LLImageDataLock lockDecodedRaw(mDecodedImageRaw);
+    LLImageDataLock lockDecodedAux(mDecodedImageAux);
+
+    if (!mDecodedRaw)
     {
         // Decode primary channels
         if (mDecodedImageRaw.isNull())
@@ -166,13 +176,10 @@ bool ImageRequest::processRequest()
             // parse formatted header
             if (!mFormattedImage->updateData())
             {
-                // Pick up errors from updateData
-                mErrorString = LLImage::getLastThreadError();
                 return true; // done (failed)
             }
-            if (0 == (mFormattedImage->getWidth() * mFormattedImage->getHeight() * mFormattedImage->getComponents()))
+            if ((mFormattedImage->getWidth() * mFormattedImage->getHeight() * mFormattedImage->getComponents()) == 0)
             {
-                mErrorString = "Invalid image size";
                 return true; // done (failed)
             }
             if (mDiscardLevel >= 0)
diff --git a/indra/llimage/llimageworker.h b/indra/llimage/llimageworker.h
index 8c43a7c32c..9e01f0bacd 100644
--- a/indra/llimage/llimageworker.h
+++ b/indra/llimage/llimageworker.h
@@ -49,7 +49,7 @@ public:
     // meant to resemble LLQueuedThread::handle_t
     typedef U32 handle_t;
     handle_t decodeImage(const LLPointer<LLImageFormatted>& image,
-                         S32 discard, BOOL needs_aux,
+                         S32 discard, bool needs_aux,
                          const LLPointer<Responder>& responder);
     size_t getPending();
     size_t update(F32 max_time_ms);
diff --git a/indra/llimage/llpngwrapper.cpp b/indra/llimage/llpngwrapper.cpp
index 24b6d34fe2..79c201b1f4 100644
--- a/indra/llimage/llpngwrapper.cpp
+++ b/indra/llimage/llpngwrapper.cpp
@@ -70,7 +70,7 @@ LLPngWrapper::~LLPngWrapper()
 }
 
 // Checks the src for a valid PNG header
-BOOL LLPngWrapper::isValidPng(U8* src)
+bool LLPngWrapper::isValidPng(U8* src)
 {
     const int PNG_BYTES_TO_CHECK = 8;
 
@@ -78,10 +78,10 @@ BOOL LLPngWrapper::isValidPng(U8* src)
     if (sig != 0)
     {
         mErrorMessage = "Invalid or corrupt PNG file";
-        return FALSE;
+        return false;
     }
 
-    return TRUE;
+    return true;
 }
 
 // Called by the libpng library when a fatal encoding or decoding error
@@ -134,7 +134,7 @@ void LLPngWrapper::writeFlush(png_structp png_ptr)
 // The scanline also begins at the bottom of
 // the image (per SecondLife conventions) instead of at the top, so we
 // must assign row-pointers in "reverse" order.
-BOOL LLPngWrapper::readPng(U8* src, S32 dataSize, LLImageRaw* rawImage, ImageInfo *infop)
+bool LLPngWrapper::readPng(U8* src, S32 dataSize, LLImageRaw* rawImage, ImageInfo *infop)
 {
     try
     {
@@ -173,6 +173,8 @@ BOOL LLPngWrapper::readPng(U8* src, S32 dataSize, LLImageRaw* rawImage, ImageInf
         // data space
         if (rawImage != NULL)
         {
+            LLImageDataLock lock(rawImage);
+
             if (!rawImage->resize(static_cast<U16>(mWidth),
                 static_cast<U16>(mHeight), mChannels))
             {
@@ -208,25 +210,25 @@ BOOL LLPngWrapper::readPng(U8* src, S32 dataSize, LLImageRaw* rawImage, ImageInf
     {
         mErrorMessage = msg.what();
         releaseResources();
-        return (FALSE);
+        return (false);
     }
     catch (std::bad_alloc&)
     {
         mErrorMessage = "LLPngWrapper";
         releaseResources();
-        return (FALSE);
+        return (false);
     }
     catch (...)
     {
         mErrorMessage = "LLPngWrapper";
         releaseResources();
         LOG_UNHANDLED_EXCEPTION("");
-        return (FALSE);
+        return (false);
     }
 
     // Clean up and return
     releaseResources();
-    return (TRUE);
+    return (true);
 }
 
 // Do transformations to normalize the input to 8-bpp RGBA
@@ -288,7 +290,7 @@ void LLPngWrapper::updateMetaData()
 
 // Method to write raw image into PNG at dest. The raw scanline begins
 // at the bottom of the image per SecondLife conventions.
-BOOL LLPngWrapper::writePng(const LLImageRaw* rawImage, U8* dest, size_t destSize)
+bool LLPngWrapper::writePng(const LLImageRaw* rawImage, U8* dest, size_t destSize)
 {
     try
     {
@@ -326,10 +328,10 @@ BOOL LLPngWrapper::writePng(const LLImageRaw* rawImage, U8* dest, size_t destSiz
         mWriteInfoPtr = png_create_info_struct(mWritePngPtr);
 
         // Setup write function
-        PngDataInfo dataPtr;
+        PngDataInfo dataPtr{};
         dataPtr.mData = dest;
         dataPtr.mOffset = 0;
-        dataPtr.mDataSize = destSize;
+        dataPtr.mDataSize = static_cast<S32>(destSize);
         png_set_write_fn(mWritePngPtr, &dataPtr, &writeDataCallback, &writeFlush);
 
         // Setup image params
@@ -369,11 +371,11 @@ BOOL LLPngWrapper::writePng(const LLImageRaw* rawImage, U8* dest, size_t destSiz
     {
         mErrorMessage = msg.what();
         releaseResources();
-        return (FALSE);
+        return (false);
     }
 
     releaseResources();
-    return TRUE;
+    return true;
 }
 
 // Cleanup various internal structures
diff --git a/indra/llimage/llpngwrapper.h b/indra/llimage/llpngwrapper.h
index f3c3d57f70..3ada8ac7c2 100644
--- a/indra/llimage/llpngwrapper.h
+++ b/indra/llimage/llpngwrapper.h
@@ -43,9 +43,9 @@ public:
         S8  mComponents;
     };
 
-    BOOL isValidPng(U8* src);
-    BOOL readPng(U8* src, S32 dataSize, LLImageRaw* rawImage, ImageInfo *infop = NULL);
-    BOOL writePng(const LLImageRaw* rawImage, U8* dst, size_t destSize);
+    bool isValidPng(U8* src);
+    bool readPng(U8* src, S32 dataSize, LLImageRaw* rawImage, ImageInfo *infop = NULL);
+    bool writePng(const LLImageRaw* rawImage, U8* dst, size_t destSize);
     U32  getFinalSize();
     const std::string& getErrorMessage();
 
diff --git a/indra/llimage/tests/llimageworker_test.cpp b/indra/llimage/tests/llimageworker_test.cpp
index 2568adf89e..36be885912 100644
--- a/indra/llimage/tests/llimageworker_test.cpp
+++ b/indra/llimage/tests/llimageworker_test.cpp
@@ -151,7 +151,7 @@ namespace tut
         ensure("LLImageDecodeThread: threaded constructor failed", mThread != NULL);
         // Insert something in the queue
         bool done = false;
-        LLImageDecodeThread::handle_t decodeHandle = mThread->decodeImage(NULL, 0, FALSE, new responder_test(&done));
+        LLImageDecodeThread::handle_t decodeHandle = mThread->decodeImage(NULL, 0, false, new responder_test(&done));
         // Verifies we get back a valid handle
         ensure("LLImageDecodeThread:  threaded decodeImage(), returned handle is null", decodeHandle != 0);
         // Wait till the thread has time to handle the work order (though it doesn't do much per work order...)