source/blender/imbuf/CMakeLists.txt

@@ -18,6 +18,7 @@ set(INC_SYS
   ${JPEG_INCLUDE_DIR}
   ${PNG_INCLUDE_DIRS}
   ${ZLIB_INCLUDE_DIRS}
+  ${OPENIMAGEIO_INCLUDE_DIRS}
 )
 
 set(SRC
@@ -29,6 +30,7 @@ set(SRC
   intern/divers.c
   intern/filetype.c
   intern/filter.c
+  intern/format_psd.cc
   intern/imageprocess.c
   intern/indexer.c
   intern/iris.c

source/blender/imbuf/IMB_imbuf.h

@@ -678,7 +678,7 @@ void IMB_sampleImageAtLocation(
  * \attention defined in readimage.c
  */
 struct ImBuf *IMB_loadifffile(
-    int file, const char *filepath, int flags, char colorspace[IM_MAX_SPACE], const char *descr);
+    int file, int flags, char colorspace[IM_MAX_SPACE], const char *descr);
 
 /**
  * \attention defined in scaling.c

source/blender/imbuf/IMB_imbuf_types.h

@@ -318,9 +318,6 @@ extern const char *imb_ext_image[];
 extern const char *imb_ext_movie[];
 extern const char *imb_ext_audio[];
 
-/** Image formats that can only be loaded via filepath. */
-extern const char *imb_ext_image_filepath_only[];
-
 /* -------------------------------------------------------------------- */
 /** \name Imbuf Color Management Flag
  *

source/blender/imbuf/intern/IMB_filetype.h

@@ -256,3 +256,16 @@ struct ImBuf *imb_load_filepath_thumbnail_webp(const char *filepath,
 bool imb_savewebp(struct ImBuf *ibuf, const char *name, int flags);
 
 /** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Format: PSD (#IMB_FTYPE_PSD)
+ * \{ */
+
+bool imb_is_a_psd(const unsigned char *buf, size_t size);
+
+struct ImBuf *imb_load_psd(const uchar *mem,
+                           size_t size,
+                           int flags,
+                           char colorspace[IM_MAX_SPACE]);
+
+/** \} */

source/blender/imbuf/intern/filetype.c

@@ -184,9 +184,9 @@ const ImFileType IMB_FILE_TYPES[] = {
     {
         .init = NULL,
         .exit = NULL,
-        .is_a = imb_is_a_photoshop,
+        .is_a = imb_is_a_psd,
-        .load = NULL,
+        .load = imb_load_psd,
-        .load_filepath = imb_load_photoshop,
+        .load_filepath = NULL,
         .load_filepath_thumbnail = NULL,
         .save = NULL,
         .flag = IM_FTYPE_FLOAT,

source/blender/imbuf/intern/format_psd.cc

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "oiio/openimageio_support.hh"
+
+#include "IMB_imbuf_types.h"
+
+OIIO_NAMESPACE_USING
+using namespace blender::imbuf;
+
+extern "C" {
+
+bool imb_is_a_psd(const uchar *mem, size_t size)
+{
+  return imb_oiio_check(mem, size, "psd");
+}
+
+ImBuf *imb_load_psd(const uchar *mem, size_t size, int flags, char colorspace[IM_MAX_SPACE])
+{
+  ImageSpec config, spec;
+  config.attribute("oiio:UnassociatedAlpha", 1);
+
+  ReadContext ctx{mem, size, "psd", IMB_FTYPE_PSD, flags};
+
+  /* PSD should obey color space information embedded in the file. */
+  ctx.use_embedded_colorspace = true;
+
+  return imb_oiio_read(ctx, config, colorspace, spec);
+}
+}

source/blender/imbuf/intern/oiio/CMakeLists.txt

@@ -18,8 +18,10 @@ set(INC_SYS
 
 set(SRC
   openimageio_api.h
+  openimageio_support.hh
 
   openimageio_api.cpp
+  openimageio_support.cc
 )
 
 set(LIB

source/blender/imbuf/intern/oiio/openimageio_api.cpp

@@ -5,278 +5,16 @@
  * \ingroup openimageio
  */
 
-#include <set>
-
-#if defined(WIN32)
-#  include "utfconv.h"
-#  define _USE_MATH_DEFINES
-#endif
-
-/* NOTE: Keep first, #BLI_path_util conflicts with OIIO's format. */
 #include "openimageio_api.h"
 #include <OpenImageIO/imageio.h>
-#include <memory>
-
-#include "MEM_guardedalloc.h"
-
-#include "BLI_blenlib.h"
-
-#include "IMB_allocimbuf.h"
-#include "IMB_colormanagement.h"
-#include "IMB_colormanagement_intern.h"
-#include "IMB_imbuf.h"
-#include "IMB_imbuf_types.h"
 
 OIIO_NAMESPACE_USING
 
-using std::string;
-using std::unique_ptr;
-
-using uchar = uchar;
-
-template<class T, class Q>
-static void fill_all_channels(T *pixels, int width, int height, int components, Q alpha)
-{
-  if (components == 2) {
-    for (int i = width * height - 1; i >= 0; i--) {
-      pixels[i * 4 + 3] = pixels[i * 2 + 1];
-      pixels[i * 4 + 2] = pixels[i * 2 + 0];
-      pixels[i * 4 + 1] = pixels[i * 2 + 0];
-      pixels[i * 4 + 0] = pixels[i * 2 + 0];
-    }
-  }
-  else if (components == 3) {
-    for (int i = width * height - 1; i >= 0; i--) {
-      pixels[i * 4 + 3] = alpha;
-      pixels[i * 4 + 2] = pixels[i * 3 + 2];
-      pixels[i * 4 + 1] = pixels[i * 3 + 1];
-      pixels[i * 4 + 0] = pixels[i * 3 + 0];
-    }
-  }
-  else if (components == 1) {
-    for (int i = width * height - 1; i >= 0; i--) {
-      pixels[i * 4 + 3] = alpha;
-      pixels[i * 4 + 2] = pixels[i];
-      pixels[i * 4 + 1] = pixels[i];
-      pixels[i * 4 + 0] = pixels[i];
-    }
-  }
-}
-
-static ImBuf *imb_oiio_load_image(
-    ImageInput *in, int width, int height, int components, int flags, bool is_alpha)
-{
-  ImBuf *ibuf;
-  int scanlinesize = width * components * sizeof(uchar);
-
-  /* allocate the memory for the image */
-  ibuf = IMB_allocImBuf(width, height, is_alpha ? 32 : 24, flags | IB_rect);
-
-  try {
-    if (!in->read_image(0,
-                        0,
-                        0,
-                        components,
-                        TypeDesc::UINT8,
-                        (uchar *)ibuf->rect + (height - 1) * scanlinesize,
-                        AutoStride,
-                        -scanlinesize,
-                        AutoStride)) {
-      std::cerr << __func__ << ": ImageInput::read_image() failed:" << std::endl
-                << in->geterror() << std::endl;
-
-      if (ibuf) {
-        IMB_freeImBuf(ibuf);
-      }
-
-      return nullptr;
-    }
-  }
-  catch (const std::exception &exc) {
-    std::cerr << exc.what() << std::endl;
-    if (ibuf) {
-      IMB_freeImBuf(ibuf);
-    }
-
-    return nullptr;
-  }
-
-  /* ImBuf always needs 4 channels */
-  fill_all_channels((uchar *)ibuf->rect, width, height, components, 0xFF);
-
-  return ibuf;
-}
-
-static ImBuf *imb_oiio_load_image_float(
-    ImageInput *in, int width, int height, int components, int flags, bool is_alpha)
-{
-  ImBuf *ibuf;
-  int scanlinesize = width * components * sizeof(float);
-
-  /* allocate the memory for the image */
-  ibuf = IMB_allocImBuf(width, height, is_alpha ? 32 : 24, flags | IB_rectfloat);
-
-  try {
-    if (!in->read_image(0,
-                        0,
-                        0,
-                        components,
-                        TypeDesc::FLOAT,
-                        (uchar *)ibuf->rect_float + (height - 1) * scanlinesize,
-                        AutoStride,
-                        -scanlinesize,
-                        AutoStride)) {
-      std::cerr << __func__ << ": ImageInput::read_image() failed:" << std::endl
-                << in->geterror() << std::endl;
-
-      if (ibuf) {
-        IMB_freeImBuf(ibuf);
-      }
-
-      return nullptr;
-    }
-  }
-  catch (const std::exception &exc) {
-    std::cerr << exc.what() << std::endl;
-    if (ibuf) {
-      IMB_freeImBuf(ibuf);
-    }
-
-    return nullptr;
-  }
-
-  /* ImBuf always needs 4 channels */
-  fill_all_channels((float *)ibuf->rect_float, width, height, components, 1.0f);
-
-  /* NOTE: Photoshop 16 bit files never has alpha with it,
-   * so no need to handle associated/unassociated alpha. */
-  return ibuf;
-}
-
 extern "C" {
 
-bool imb_is_a_photoshop(const uchar *mem, size_t size)
-{
-  const uchar magic[4] = {'8', 'B', 'P', 'S'};
-  if (size < sizeof(magic)) {
-    return false;
-  }
-  return memcmp(magic, mem, sizeof(magic)) == 0;
-}
-
-int imb_save_photoshop(struct ImBuf *ibuf, const char * /*name*/, int flags)
-{
-  if (flags & IB_mem) {
-    std::cerr << __func__ << ": Photoshop PSD-save: Create PSD in memory"
-              << " currently not supported" << std::endl;
-    imb_addencodedbufferImBuf(ibuf);
-    ibuf->encodedsize = 0;
-    return 0;
-  }
-
-  return 0;
-}
-
-struct ImBuf *imb_load_photoshop(const char *filename, int flags, char colorspace[IM_MAX_SPACE])
-{
-  struct ImBuf *ibuf = nullptr;
-  int width, height, components;
-  bool is_float, is_alpha, is_half;
-  int basesize;
-  char file_colorspace[IM_MAX_SPACE];
-  const bool is_colorspace_manually_set = (colorspace[0] != '\0');
-
-  /* load image from file through OIIO */
-  if (IMB_ispic_type_matches(filename, IMB_FTYPE_PSD) == 0) {
-    return nullptr;
-  }
-
-  colorspace_set_default_role(colorspace, IM_MAX_SPACE, COLOR_ROLE_DEFAULT_BYTE);
-
-  unique_ptr<ImageInput> in(ImageInput::create(filename));
-  if (!in) {
-    std::cerr << __func__ << ": ImageInput::create() failed:" << std::endl
-              << OIIO_NAMESPACE::geterror() << std::endl;
-    return nullptr;
-  }
-
-  ImageSpec spec, config;
-  config.attribute("oiio:UnassociatedAlpha", int(1));
-
-  if (!in->open(filename, spec, config)) {
-    std::cerr << __func__ << ": ImageInput::open() failed:" << std::endl
-              << in->geterror() << std::endl;
-    return nullptr;
-  }
-
-  if (!is_colorspace_manually_set) {
-    string ics = spec.get_string_attribute("oiio:ColorSpace");
-    BLI_strncpy(file_colorspace, ics.c_str(), IM_MAX_SPACE);
-
-    /* Only use color-spaces exist. */
-    if (colormanage_colorspace_get_named(file_colorspace)) {
-      strcpy(colorspace, file_colorspace);
-    }
-    else {
-      std::cerr << __func__ << ": The embed colorspace (\"" << file_colorspace
-                << "\") not supported in existent OCIO configuration file. Fallback "
-                << "to system default colorspace (\"" << colorspace << "\")." << std::endl;
-    }
-  }
-
-  width = spec.width;
-  height = spec.height;
-  components = spec.nchannels;
-  is_alpha = spec.alpha_channel != -1;
-  basesize = spec.format.basesize();
-  is_float = basesize > 1;
-  is_half = spec.format == TypeDesc::HALF;
-
-  /* we only handle certain number of components */
-  if (!(components >= 1 && components <= 4)) {
-    if (in) {
-      in->close();
-    }
-    return nullptr;
-  }
-
-  if (is_float) {
-    ibuf = imb_oiio_load_image_float(in.get(), width, height, components, flags, is_alpha);
-  }
-  else {
-    ibuf = imb_oiio_load_image(in.get(), width, height, components, flags, is_alpha);
-  }
-
-  if (in) {
-    in->close();
-  }
-
-  if (!ibuf) {
-    return nullptr;
-  }
-
-  /* ImBuf always needs 4 channels */
-  ibuf->ftype = IMB_FTYPE_PSD;
-  ibuf->channels = 4;
-  ibuf->planes = (3 + (is_alpha ? 1 : 0)) * 4 << basesize;
-  ibuf->flags |= (is_float && is_half) ? IB_halffloat : 0;
-
-  try {
-    return ibuf;
-  }
-  catch (const std::exception &exc) {
-    std::cerr << exc.what() << std::endl;
-    if (ibuf) {
-      IMB_freeImBuf(ibuf);
-    }
-
-    return nullptr;
-  }
-}
-
 int OIIO_getVersionHex(void)
 {
   return openimageio_version();
 }
 
-} /* export "C" */
+} /* extern "C" */

source/blender/imbuf/intern/oiio/openimageio_api.h

@@ -7,20 +7,10 @@
 
 #pragma once
 
-#include <stdio.h>
-
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-struct ImBuf;
-
-bool imb_is_a_photoshop(const unsigned char *mem, size_t size);
-
-int imb_save_photoshop(struct ImBuf *ibuf, const char *name, int flags);
-
-struct ImBuf *imb_load_photoshop(const char *name, int flags, char *colorspace);
-
 int OIIO_getVersionHex(void);
 
 #ifdef __cplusplus

source/blender/imbuf/intern/oiio/openimageio_support.cc

@@ -0,0 +1,398 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "openimageio_support.hh"
+
+#include "BLI_blenlib.h"
+
+#include "BKE_idprop.h"
+#include "DNA_ID.h" /* ID property definitions. */
+
+#include "IMB_allocimbuf.h"
+#include "IMB_colormanagement.h"
+#include "IMB_metadata.h"
+
+OIIO_NAMESPACE_USING
+
+using std::string;
+using std::unique_ptr;
+
+namespace blender::imbuf {
+
+/* An OIIO IOProxy used during file packing to write into an in-memory #ImBuf buffer. */
+class ImBufMemWriter : public Filesystem::IOProxy {
+ public:
+  ImBufMemWriter(ImBuf *ibuf) : IOProxy("", Write), ibuf_(ibuf)
+  {
+  }
+
+  const char *proxytype() const override
+  {
+    return "ImBufMemWriter";
+  }
+
+  size_t write(const void *buf, size_t size) override
+  {
+    size = pwrite(buf, size, m_pos);
+    m_pos += size;
+    return size;
+  }
+
+  size_t pwrite(const void *buf, size_t size, int64_t offset) override
+  {
+    /* If buffer is too small increase it. */
+    size_t end = offset + size;
+    while (end > ibuf_->encodedbuffersize) {
+      if (!imb_enlargeencodedbufferImBuf(ibuf_)) {
+        /* Out of memory. */
+        return 0;
+      }
+    }
+
+    memcpy(ibuf_->encodedbuffer + offset, buf, size);
+
+    if (end > ibuf_->encodedsize) {
+      ibuf_->encodedsize = end;
+    }
+
+    return size;
+  }
+
+  size_t size() const override
+  {
+    return ibuf_->encodedsize;
+  }
+
+ private:
+  ImBuf *ibuf_;
+};
+
+/* Utility to in-place expand an n-component pixel buffer into a 4-component buffer. */
+template<typename T>
+static void fill_all_channels(T *pixels, int width, int height, int components, T alpha)
+{
+  const int64_t pixel_count = int64_t(width) * height;
+  if (components == 3) {
+    for (int64_t i = 0; i < pixel_count; i++) {
+      pixels[i * 4 + 3] = alpha;
+    }
+  }
+  else if (components == 1) {
+    for (int64_t i = 0; i < pixel_count; i++) {
+      pixels[i * 4 + 3] = alpha;
+      pixels[i * 4 + 2] = pixels[i * 4 + 0];
+      pixels[i * 4 + 1] = pixels[i * 4 + 0];
+    }
+  }
+  else if (components == 2) {
+    for (int64_t i = 0; i < pixel_count; i++) {
+      pixels[i * 4 + 3] = pixels[i * 4 + 1];
+      pixels[i * 4 + 2] = pixels[i * 4 + 0];
+      pixels[i * 4 + 1] = pixels[i * 4 + 0];
+    }
+  }
+}
+
+template<typename T>
+static ImBuf *load_pixels(
+    ImageInput *in, int width, int height, int channels, int flags, bool use_all_planes)
+{
+  /* Allocate the ImBuf for the image. */
+  constexpr bool is_float = sizeof(T) > 1;
+  const uint format_flag = is_float ? IB_rectfloat : IB_rect;
+  const uint ibuf_flags = (flags & IB_test) ? 0 : format_flag;
+  const int planes = use_all_planes ? 32 : 8 * channels;
+  ImBuf *ibuf = IMB_allocImBuf(width, height, planes, ibuf_flags);
+  if (!ibuf) {
+    return nullptr;
+  }
+
+  /* No need to load actual pixel data during the test phase. */
+  if (flags & IB_test) {
+    return ibuf;
+  }
+
+  /* Calculate an appropriate stride to read n-channels directly into
+   * the ImBuf 4-channel layout. */
+  const stride_t ibuf_xstride = sizeof(T) * 4;
+  const stride_t ibuf_ystride = ibuf_xstride * width;
+  const TypeDesc format = is_float ? TypeDesc::FLOAT : TypeDesc::UINT8;
+  uchar *rect = is_float ? reinterpret_cast<uchar *>(ibuf->rect_float) :
+                           reinterpret_cast<uchar *>(ibuf->rect);
+  void *ibuf_data = rect + ((stride_t(height) - 1) * ibuf_ystride);
+
+  bool ok = in->read_image(
+      0, 0, 0, channels, format, ibuf_data, ibuf_xstride, -ibuf_ystride, AutoStride);
+  if (!ok) {
+    fprintf(stderr, "ImageInput::read_image() failed: %s\n", in->geterror().c_str());
+
+    IMB_freeImBuf(ibuf);
+    return nullptr;
+  }
+
+  /* ImBuf always needs 4 channels */
+  const T alpha_fill = is_float ? 1.0f : 0xFF;
+  fill_all_channels<T>(reinterpret_cast<T *>(rect), width, height, channels, alpha_fill);
+
+  return ibuf;
+}
+
+static void set_colorspace_name(char colorspace[IM_MAX_SPACE],
+                                const ReadContext &ctx,
+                                const ImageSpec &spec,
+                                bool is_float)
+{
+  const bool is_colorspace_set = (colorspace[0] != '\0');
+  if (is_colorspace_set) {
+    return;
+  }
+
+  /* Use a default role unless otherwise specified. */
+  if (ctx.use_colorspace_role >= 0) {
+    colorspace_set_default_role(colorspace, IM_MAX_SPACE, ctx.use_colorspace_role);
+  }
+  else if (is_float) {
+    colorspace_set_default_role(colorspace, IM_MAX_SPACE, COLOR_ROLE_DEFAULT_FLOAT);
+  }
+  else {
+    colorspace_set_default_role(colorspace, IM_MAX_SPACE, COLOR_ROLE_DEFAULT_BYTE);
+  }
+
+  /* Override if necessary. */
+  if (ctx.use_embedded_colorspace) {
+    string ics = spec.get_string_attribute("oiio:ColorSpace");
+    char file_colorspace[IM_MAX_SPACE];
+    BLI_strncpy(file_colorspace, ics.c_str(), IM_MAX_SPACE);
+
+    /* Only use color-spaces that exist. */
+    if (colormanage_colorspace_get_named(file_colorspace)) {
+      BLI_strncpy(colorspace, file_colorspace, IM_MAX_SPACE);
+    }
+  }
+}
+
+/**
+ * Get an #ImBuf filled in with pixel data and associated metadata using the provided ImageInput.
+ */
+static ImBuf *get_oiio_ibuf(ImageInput *in, const ReadContext &ctx, char colorspace[IM_MAX_SPACE])
+{
+  const ImageSpec &spec = in->spec();
+  const int width = spec.width;
+  const int height = spec.height;
+  const int channels = spec.nchannels;
+  const bool has_alpha = spec.alpha_channel != -1;
+  const bool is_float = spec.format.basesize() > 1;
+
+  if (channels < 1 || channels > 4) {
+    return nullptr;
+  }
+
+  const bool use_all_planes = has_alpha || ctx.use_all_planes;
+
+  ImBuf *ibuf = nullptr;
+  if (is_float) {
+    ibuf = load_pixels<float>(in, width, height, channels, ctx.flags, use_all_planes);
+    ibuf->channels = 4;
+  }
+  else {
+    ibuf = load_pixels<uchar>(in, width, height, channels, ctx.flags, use_all_planes);
+  }
+
+  /* Fill in common ibuf properties. */
+  if (ibuf) {
+    ibuf->ftype = ctx.file_type;
+    ibuf->flags |= (spec.format == TypeDesc::HALF) ? IB_halffloat : 0;
+
+    set_colorspace_name(colorspace, ctx, spec, is_float);
+
+    float x_res = spec.get_float_attribute("XResolution", 0.0f);
+    float y_res = spec.get_float_attribute("YResolution", 0.0f);
+    if (x_res > 0.0f && y_res > 0.0f) {
+      double scale = 1.0;
+      auto unit = spec.get_string_attribute("ResolutionUnit", "");
+      if (unit == "in" || unit == "inch") {
+        scale = 100.0 / 2.54;
+      }
+      else if (unit == "cm") {
+        scale = 100.0;
+      }
+      ibuf->ppm[0] = scale * x_res;
+      ibuf->ppm[1] = scale * y_res;
+    }
+
+    /* Transfer metadata to the ibuf if necessary. */
+    if (ctx.flags & IB_metadata) {
+      IMB_metadata_ensure(&ibuf->metadata);
+      ibuf->flags |= (spec.extra_attribs.empty()) ? 0 : IB_metadata;
+
+      for (const auto &attrib : spec.extra_attribs) {
+        IMB_metadata_set_field(ibuf->metadata, attrib.name().c_str(), attrib.get_string().c_str());
+      }
+    }
+  }
+
+  return ibuf;
+}
+
+/**
+ * Returns an ImageInput for the precise `format` requested using the provided IOMemReader.
+ * If successful, the ImageInput will be opened and ready for operations. Null will be returned if
+ * the format was not found or if the open call fails.
+ */
+static unique_ptr<ImageInput> get_oiio_reader(const char *format,
+                                              const ImageSpec &config,
+                                              Filesystem::IOMemReader &mem_reader,
+                                              ImageSpec &r_newspec)
+{
+  /* Attempt to create a reader based on the passed in format. */
+  unique_ptr<ImageInput> in = ImageInput::create(format);
+  if (!in) {
+    return nullptr;
+  }
+
+  /* Open the reader using the ioproxy. */
+  in->set_ioproxy(&mem_reader);
+  bool ok = in->open("", r_newspec, config);
+  if (!ok) {
+    in.reset();
+  }
+
+  return in;
+}
+
+bool imb_oiio_check(const uchar *mem, size_t mem_size, const char *file_format)
+{
+  ImageSpec config, spec;
+
+  /* This memory proxy must remain alive for the full duration of the read. */
+  Filesystem::IOMemReader mem_reader(cspan<uchar>(mem, mem_size));
+  unique_ptr<ImageInput> in = get_oiio_reader(file_format, config, mem_reader, spec);
+  return in ? true : false;
+}
+
+ImBuf *imb_oiio_read(const ReadContext &ctx,
+                     const ImageSpec &config,
+                     char colorspace[IM_MAX_SPACE],
+                     ImageSpec &r_newspec)
+{
+  /* This memory proxy must remain alive for the full duration of the read. */
+  Filesystem::IOMemReader mem_reader(cspan<uchar>(ctx.mem_start, ctx.mem_size));
+  unique_ptr<ImageInput> in = get_oiio_reader(ctx.file_format, config, mem_reader, r_newspec);
+  if (!in) {
+    return nullptr;
+  }
+
+  return get_oiio_ibuf(in.get(), ctx, colorspace);
+}
+
+bool imb_oiio_write(const WriteContext &ctx, const char *filepath, const ImageSpec &file_spec)
+{
+  unique_ptr<ImageOutput> out = ImageOutput::create(ctx.file_format);
+  if (!out) {
+    return false;
+  }
+
+  auto write_op = [&out, &ctx]() {
+    return out->write_image(
+        ctx.mem_format, ctx.mem_start, ctx.mem_xstride, -ctx.mem_ystride, AutoStride);
+  };
+
+  bool ok = false;
+  if (ctx.flags & IB_mem) {
+    /* This memory proxy must remain alive for the full duration of the write. */
+    ImBufMemWriter writer(ctx.ibuf);
+
+    imb_addencodedbufferImBuf(ctx.ibuf);
+    out->set_ioproxy(&writer);
+    out->open("", file_spec);
+    ok = write_op();
+  }
+  else {
+    out->open(filepath, file_spec);
+    ok = write_op();
+  }
+
+  out->close();
+  return ok;
+}
+
+WriteContext imb_create_write_context(const char *file_format,
+                                      ImBuf *ibuf,
+                                      int flags,
+                                      bool prefer_float)
+{
+  WriteContext ctx{};
+  ctx.file_format = file_format;
+  ctx.ibuf = ibuf;
+  ctx.flags = flags;
+
+  const int width = ibuf->x;
+  const int height = ibuf->y;
+  const bool use_float = prefer_float && (ibuf->rect_float != nullptr);
+  if (use_float) {
+    const int mem_channels = ibuf->channels ? ibuf->channels : 4;
+    ctx.mem_xstride = sizeof(float) * mem_channels;
+    ctx.mem_ystride = width * ctx.mem_xstride;
+    ctx.mem_format = TypeDesc::FLOAT;
+    ctx.mem_start = reinterpret_cast<uchar *>(ibuf->rect_float);
+  }
+  else {
+    const int mem_channels = 4;
+    ctx.mem_xstride = sizeof(uchar) * mem_channels;
+    ctx.mem_ystride = width * ctx.mem_xstride;
+    ctx.mem_format = TypeDesc::UINT8;
+    ctx.mem_start = reinterpret_cast<uchar *>(ibuf->rect);
+  }
+
+  /* We always write using a negative y-stride so ensure we start at the end. */
+  ctx.mem_start = ctx.mem_start + ((stride_t(height) - 1) * ctx.mem_ystride);
+
+  return ctx;
+}
+
+ImageSpec imb_create_write_spec(const WriteContext &ctx, int file_channels, TypeDesc data_format)
+{
+  const int width = ctx.ibuf->x;
+  const int height = ctx.ibuf->y;
+  ImageSpec file_spec(width, height, file_channels, data_format);
+
+  /* Populate the spec with all common attributes.
+   *
+   * Care must be taken with the metadata:
+   *  - It should be processed first, before the "Resolution" metadata below, to
+   *    ensure the proper values end up in the ImageSpec
+   *  - It needs to filter format-specific metadata that may no longer apply to
+   *    the current format being written (e.g. metadata for tiff being written to a png)
+   */
+
+  if (ctx.ibuf->metadata) {
+    for (IDProperty *prop = static_cast<IDProperty *>(ctx.ibuf->metadata->data.group.first); prop;
+         prop = prop->next) {
+      if (prop->type == IDP_STRING) {
+        /* If this property has a prefixed name (oiio:, tiff:, etc.) and it belongs to
+         * oiio or a different format, then skip. */
+        if (char *colon = strchr(prop->name, ':')) {
+          std::string prefix(prop->name, colon);
+          Strutil::to_lower(prefix);
+          if (prefix == "oiio" ||
+              (!STREQ(prefix.c_str(), ctx.file_format) && OIIO::is_imageio_format_name(prefix))) {
+            /* Skip this attribute. */
+            continue;
+          }
+        }
+
+        file_spec.attribute(prop->name, IDP_String(prop));
+      }
+    }
+  }
+
+  if (ctx.ibuf->ppm[0] > 0.0 && ctx.ibuf->ppm[1] > 0.0) {
+    /* More OIIO formats support inch than meter. */
+    file_spec.attribute("ResolutionUnit", "in");
+    file_spec.attribute("XResolution", float(ctx.ibuf->ppm[0] * 0.0254));
+    file_spec.attribute("YResolution", float(ctx.ibuf->ppm[1] * 0.0254));
+  }
+
+  return file_spec;
+}
+
+}  // namespace blender::imbuf

source/blender/imbuf/intern/oiio/openimageio_support.hh

@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+#include <memory>
+
+#include <OpenImageIO/filesystem.h>
+#include <OpenImageIO/imageio.h>
+
+#include "BLI_sys_types.h"
+
+#include "IMB_imbuf.h"
+#include "IMB_imbuf_types.h"
+
+namespace blender::imbuf {
+
+/**
+ * Parameters and settings used while reading image formats.
+ */
+struct ReadContext {
+  const uchar *mem_start;
+  const size_t mem_size;
+  const char *file_format;
+  const eImbFileType file_type;
+  const int flags;
+
+  /* Override the automatic color-role choice with the value specified here. */
+  int use_colorspace_role = -1;
+
+  /* Allocate and use all ImBuf image planes even if the image has fewer. */
+  bool use_all_planes = false;
+
+  /* Use the colorspace provided in the image metadata when available. */
+  bool use_embedded_colorspace = false;
+};
+
+/**
+ * Parameters and settings used while writing image formats.
+ */
+struct WriteContext {
+  const char *file_format;
+  ImBuf *ibuf;
+
+  OIIO::stride_t mem_xstride;
+  OIIO::stride_t mem_ystride;
+  OIIO::TypeDesc mem_format;
+  uchar *mem_start;
+
+  int flags;
+};
+
+/**
+ * Check to see if we can load and open the given file format.
+ */
+bool imb_oiio_check(const uchar *mem, size_t mem_size, const char *file_format);
+
+/**
+ * The primary method for reading data into an #ImBuf.
+ *
+ * During the `IB_test` phase of loading, the `colorspace` parameter will be populated
+ * with the appropriate colorspace name.
+ *
+ * Upon return, the `r_newspec` parameter will contain image format information
+ * which can be inspected afterwards if necessary.
+ */
+ImBuf *imb_oiio_read(const ReadContext &ctx,
+                     const OIIO::ImageSpec &config,
+                     char colorspace[IM_MAX_SPACE],
+                     OIIO::ImageSpec &r_newspec);
+
+/**
+ * The primary method for writing data from an #ImBuf to either a physical or in-memory
+ * destination.
+ *
+ * The `file_spec` parameter will typically come from #imb_create_write_spec.
+ */
+bool imb_oiio_write(const WriteContext &ctx,
+                    const char *filepath,
+                    const OIIO::ImageSpec &file_spec);
+
+/**
+ * Create a #WriteContext based on the provided #ImBuf and format information.
+ *
+ * If the provided #ImBuf contains both byte and float buffers, the `prefer_float`
+ * flag controls which buffer to use. By default, if a float buffer exists it will
+ * be used.
+ */
+WriteContext imb_create_write_context(const char *file_format,
+                                      ImBuf *ibuf,
+                                      int flags,
+                                      bool prefer_float = true);
+
+/**
+ * Returns an ImageSpec filled in with all common attributes associated with the #ImBuf
+ * provided as part of the #WriteContext.
+ *
+ * This includes optional metadata that has been attached to the #ImBuf and which should be
+ * written to the new file as necessary.
+ */
+OIIO::ImageSpec imb_create_write_spec(const WriteContext &ctx,
+                                      int file_channels,
+                                      OIIO::TypeDesc data_format);
+
+}  // namespace blender::imbuf

source/blender/imbuf/intern/openexr/openexr_api.cpp

@@ -441,7 +441,7 @@ static void openexr_header_metadata(Header *header, struct ImBuf *ibuf)
     IDProperty *prop;
 
     for (prop = (IDProperty *)ibuf->metadata->data.group.first; prop; prop = prop->next) {
-      if (prop->type == IDP_STRING) {
+      if (prop->type == IDP_STRING && !STREQ(prop->name, "compression")) {
         header->insert(prop->name, StringAttribute(IDP_String(prop)));
       }
     }

source/blender/imbuf/intern/readimage.c

@@ -114,44 +114,7 @@ ImBuf *IMB_ibImageFromMemory(
   return NULL;
 }
 
-static ImBuf *IMB_ibImageFromFile(const char *filepath,
+ImBuf *IMB_loadifffile(int file, int flags, char colorspace[IM_MAX_SPACE], const char *descr)
-                                  int flags,
-                                  char colorspace[IM_MAX_SPACE],
-                                  const char *descr)
-{
-  ImBuf *ibuf;
-  const ImFileType *type;
-  char effective_colorspace[IM_MAX_SPACE] = "";
-
-  if (colorspace) {
-    BLI_strncpy(effective_colorspace, colorspace, sizeof(effective_colorspace));
-  }
-
-  for (type = IMB_FILE_TYPES; type < IMB_FILE_TYPES_LAST; type++) {
-    if (type->load_filepath) {
-      ibuf = type->load_filepath(filepath, flags, effective_colorspace);
-      if (ibuf) {
-        imb_handle_alpha(ibuf, flags, colorspace, effective_colorspace);
-        return ibuf;
-      }
-    }
-  }
-
-  if ((flags & IB_test) == 0) {
-    fprintf(stderr, "%s: unknown fileformat (%s)\n", __func__, descr);
-  }
-
-  return NULL;
-}
-
-static bool imb_is_filepath_format(const char *filepath)
-{
-  /* return true if this is one of the formats that can't be loaded from memory */
-  return BLI_path_extension_check_array(filepath, imb_ext_image_filepath_only);
-}
-
-ImBuf *IMB_loadifffile(
-    int file, const char *filepath, int flags, char colorspace[IM_MAX_SPACE], const char *descr)
 {
   ImBuf *ibuf;
   uchar *mem;
@@ -161,10 +124,6 @@ ImBuf *IMB_loadifffile(
     return NULL;
   }
 
-  if (imb_is_filepath_format(filepath)) {
-    return IMB_ibImageFromFile(filepath, flags, colorspace, descr);
-  }
-
   size = BLI_file_descriptor_size(file);
 
   imb_mmap_lock();
@@ -198,7 +157,7 @@ ImBuf *IMB_loadiffname(const char *filepath, int flags, char colorspace[IM_MAX_S
     return NULL;
   }
 
-  ibuf = IMB_loadifffile(file, filepath, flags, colorspace, filepath);
+  ibuf = IMB_loadifffile(file, flags, colorspace, filepath);
 
   if (ibuf) {
     BLI_strncpy(ibuf->name, filepath, sizeof(ibuf->name));
@@ -277,7 +236,7 @@ ImBuf *IMB_testiffname(const char *filepath, int flags)
     return NULL;
   }
 
-  ibuf = IMB_loadifffile(file, filepath, flags | IB_test | IB_multilayer, colorspace, filepath);
+  ibuf = IMB_loadifffile(file, flags | IB_test | IB_multilayer, colorspace, filepath);
 
   if (ibuf) {
     BLI_strncpy(ibuf->name, filepath, sizeof(ibuf->name));

source/blender/imbuf/intern/util.c

@@ -67,13 +67,6 @@ const char *imb_ext_image[] = {
     NULL,
 };
 
-const char *imb_ext_image_filepath_only[] = {
-    ".psd",
-    ".pdd",
-    ".psb",
-    NULL,
-};
-
 const char *imb_ext_movie[] = {
     ".avi",  ".flc", ".mov", ".movie", ".mp4",  ".m4v",  ".m2v", ".m2t",  ".m2ts", ".mts",
     ".ts",   ".mv",  ".avs", ".wmv",   ".ogv",  ".ogg",  ".r3d", ".dv",   ".mpeg", ".mpg",

source/blender/python/generic/imbuf_py_api.c

@@ -480,7 +480,7 @@ static PyObject *M_imbuf_load(PyObject *UNUSED(self), PyObject *args, PyObject *
     return NULL;
   }
 
-  ImBuf *ibuf = IMB_loadifffile(file, filepath, IB_rect, NULL, filepath);
+  ImBuf *ibuf = IMB_loadifffile(file, IB_rect, NULL, filepath);
 
   close(file);