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Simplify jpeg-parser a bit
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Comment out unused members in MPOEntry and clarify FIXME.
Replace pointers with references.
Use explicit types for parameters in parse callbacks.
Flatten jpeg_get_mpo_data().
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@qarkai
qarkai committed Jan 14, 2025
1 parent f428cc6 commit 34bab77
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Showing 2 changed files with 122 additions and 124 deletions.
222 changes: 110 additions & 112 deletions src/jpeg-parser.cc
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Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,7 @@
#include "jpeg-parser.h"

#include <cstring>
#include <functional>


gboolean is_jpeg_container(const guchar *data, guint size)
Expand Down Expand Up @@ -108,69 +109,65 @@ static guint32 tiff_byte_get_int32(const guchar *f, TiffByteOrder bo)
return GUINT32_FROM_BE(align_buf); // NOLINT
}

static gint tiff_directory_offset(const guchar *data, const guint len,
guint *offset, TiffByteOrder *bo)
static gboolean tiff_directory_offset(const guchar *data, const guint len,
guint &offset, TiffByteOrder &bo)
{
if (len < 8) return FALSE;

if (memcmp(data, "II", 2) == 0)
{
*bo = TIFF_BYTE_ORDER_INTEL;
bo = TIFF_BYTE_ORDER_INTEL;
}
else if (memcmp(data, "MM", 2) == 0)
{
*bo = TIFF_BYTE_ORDER_MOTOROLA;
bo = TIFF_BYTE_ORDER_MOTOROLA;
}
else
{
return FALSE;
}

if (tiff_byte_get_int16(data + 2, *bo) != 0x002A)
if (tiff_byte_get_int16(data + 2, bo) != 0x002A)
{
return FALSE;
}

*offset = tiff_byte_get_int32(data + 4, *bo);
offset = tiff_byte_get_int32(data + 4, bo);

return (*offset < len);
return offset < len;
}

using FuncParseIFDEntry = gint (*)(const guchar *, guint, guint, TiffByteOrder, gpointer);

using FuncParseIFDEntry = std::function<gint(const guchar *, guint, TiffByteOrder)>;

static gint tiff_parse_IFD_table(const guchar *tiff, guint offset,
guint size, TiffByteOrder bo,
guint *next_offset,
FuncParseIFDEntry parse_entry, gpointer data)
const FuncParseIFDEntry &parse_entry,
guint *next_offset = nullptr)
{
guint count;
guint i;
guint next;


/* We should be able to read number of entries in IFD0) */
if (size < offset + 2) return -1;

count = tiff_byte_get_int16(tiff + offset, bo);
guint count = tiff_byte_get_int16(tiff + offset, bo);
offset += 2;
/* Entries and next IFD offset must be readable */
if (size < offset + count * TIFF_TIFD_SIZE + 4) return -1;

for (i = 0; i < count; i++)
for (guint i = 0; i < count; i++)
{
parse_entry(tiff, offset + (i * TIFF_TIFD_SIZE), size, bo, data);
parse_entry(tiff, offset + (i * TIFF_TIFD_SIZE), bo);
}

next = tiff_byte_get_int32(tiff + offset + (count * TIFF_TIFD_SIZE), bo);
if (next_offset) *next_offset = next;
if (next_offset)
{
*next_offset = tiff_byte_get_int32(tiff + offset + (count * TIFF_TIFD_SIZE), bo);
}

return 0;
}

static gint mpo_parse_Index_IFD_entry(const guchar *tiff, guint offset,
guint size, TiffByteOrder bo,
gpointer data)
guint size, TiffByteOrder bo,
MPOData &mpo)
{
guint tag;
guint format;
Expand All @@ -179,8 +176,6 @@ static gint mpo_parse_Index_IFD_entry(const guchar *tiff, guint offset,
guint data_offset;
guint data_length;

auto mpo = static_cast<MPOData *>(data);

tag = tiff_byte_get_int16(tiff + offset + TIFF_TIFD_OFFSET_TAG, bo);
format = tiff_byte_get_int16(tiff + offset + TIFF_TIFD_OFFSET_FORMAT, bo);
count = tiff_byte_get_int32(tiff + offset + TIFF_TIFD_OFFSET_COUNT, bo);
Expand All @@ -189,68 +184,66 @@ static gint mpo_parse_Index_IFD_entry(const guchar *tiff, guint offset,

if (tag == 0xb000)
{
mpo->version = data_val;
DEBUG_1(" mpo version %x", mpo->version);
mpo.version = data_val;
DEBUG_1(" mpo version %x", mpo.version);
}
else if (tag == 0xb001)
{
mpo->num_images = data_val;
DEBUG_1(" num images %x", mpo->num_images);
mpo.num_images = data_val;
DEBUG_1(" num images %x", mpo.num_images);
}
else if (tag == 0xb002)
{
guint i;
data_offset = data_val;
data_length = count;
if (size < data_offset || size < data_offset + data_length)
{
return -1;
}
if (count != mpo->num_images * 16)
if (count != mpo.num_images * 16)
{
return -1;
}

mpo->images = g_new0(MPOEntry, mpo->num_images);
mpo.images = g_new0(MPOEntry, mpo.num_images);

for (i = 0; i < mpo->num_images; i++) {
for (guint i = 0; i < mpo.num_images; i++)
{
guint image_attr = tiff_byte_get_int32(tiff + data_offset + (i * 16), bo);
mpo->images[i].type_code = image_attr & 0xffffff;
mpo->images[i].representative = !!(image_attr & 0x20000000);
mpo->images[i].dependent_child = !!(image_attr & 0x40000000);
mpo->images[i].dependent_parent = !!(image_attr & 0x80000000);
mpo->images[i].length = tiff_byte_get_int32(tiff + data_offset + (i * 16) + 4, bo);
mpo->images[i].offset = tiff_byte_get_int32(tiff + data_offset + (i * 16) + 8, bo);
mpo->images[i].dep1 = tiff_byte_get_int16(tiff + data_offset + (i * 16) + 12, bo);
mpo->images[i].dep2 = tiff_byte_get_int16(tiff + data_offset + (i * 16) + 14, bo);
mpo.images[i].type_code = image_attr & 0xffffff;
mpo.images[i].representative = !!(image_attr & 0x20000000);
mpo.images[i].dependent_child = !!(image_attr & 0x40000000);
mpo.images[i].dependent_parent = !!(image_attr & 0x80000000);
mpo.images[i].length = tiff_byte_get_int32(tiff + data_offset + (i * 16) + 4, bo);
mpo.images[i].offset = tiff_byte_get_int32(tiff + data_offset + (i * 16) + 8, bo);
mpo.images[i].dep1 = tiff_byte_get_int16(tiff + data_offset + (i * 16) + 12, bo);
mpo.images[i].dep2 = tiff_byte_get_int16(tiff + data_offset + (i * 16) + 14, bo);

if (i == 0)
{
mpo->images[i].offset = 0;
mpo.images[i].offset = 0;
}
else
{
mpo->images[i].offset += mpo->mpo_offset;
mpo.images[i].offset += mpo.mpo_offset;
}

DEBUG_1(" image %x %x %x", image_attr, mpo->images[i].length, mpo->images[i].offset);
DEBUG_1(" image %x %x %x", image_attr, mpo.images[i].length, mpo.images[i].offset);
}
}

return 0;
}

static gint mpo_parse_Attributes_IFD_entry(const guchar *tiff, guint offset,
guint, TiffByteOrder bo,
gpointer data)
TiffByteOrder bo,
MPOEntry &mpe)
{
guint tag;
guint format;
guint count;
guint data_val;

auto mpe = static_cast<MPOEntry *>(data);

tag = tiff_byte_get_int16(tiff + offset + TIFF_TIFD_OFFSET_TAG, bo);
format = tiff_byte_get_int16(tiff + offset + TIFF_TIFD_OFFSET_FORMAT, bo);
count = tiff_byte_get_int32(tiff + offset + TIFF_TIFD_OFFSET_COUNT, bo);
Expand All @@ -260,33 +253,34 @@ static gint mpo_parse_Attributes_IFD_entry(const guchar *tiff, guint offset,
switch (tag)
{
case 0xb000:
mpe->MPFVersion = data_val;
mpe.MPFVersion = data_val;
DEBUG_1(" mpo version %x", data_val);
break;
case 0xb101:
mpe->MPIndividualNum = data_val;
DEBUG_1(" Individual Image Number %x", mpe->MPIndividualNum);
mpe.MPIndividualNum = data_val;
DEBUG_1(" Individual Image Number %x", mpe.MPIndividualNum);
break;
case 0xb201:
mpe->PanOrientation = data_val;
mpe.PanOrientation = data_val;
break;
/**
@FIXME
Panorama Scanning Orientation PanOrientation 45569 B201 LONG 1 \n
Panorama Horizontal Overlap PanOverlap_H 45570 B202 RATIONAL 1 \n
Panorama Vertical Overlap PanOverlap_V 45571 B203 RATIONAL 1 \n
Base Viewpoint Number BaseViewpointNum 45572 B204 LONG 1 \n
Convergence Angle ConvergenceAngle 45573 B205 SRATIONAL 1 \n
Baseline Length BaselineLength 45574 B206 RATIONAL 1 \n
Divergence Angle VerticalDivergence 45575 B207 SRATIONAL 1 \n
Horizontal Axis Distance AxisDistance_X 45576 B208 SRATIONAL 1 \n
Vertical Axis Distance AxisDistance_Y 45577 B209 SRATIONAL 1 \n
Collimation Axis Distance AxisDistance_Z 45578 B20A SRATIONAL 1 \n
Yaw Angle YawAngle 45579 B20B SRATIONAL 1 \n
Pitch Angle PitchAngle 45580 B20C SRATIONAL 1 \n
Roll Angle RollAngle 45581 B20D
*/
/**
@FIXME See section 5.2.4. MP Attribute IFD of
CIPA DC-007-Translation-2021 Multi-Picture Format
https://www.cipa.jp/std/documents/download_e.html?CIPA_DC-007-2021_E
Tag Name Field Name Tag ID (Dec/Hex) Type Count
Panorama Horizontal Overlap PanOverlap_H 45570 B202 RATIONAL 1
Panorama Vertical Overlap PanOverlap_V 45571 B203 RATIONAL 1
Base Viewpoint Number BaseViewpointNum 45572 B204 LONG 1
Convergence Angle ConvergenceAngle 45573 B205 SRATIONAL 1
Baseline Length BaselineLength 45574 B206 RATIONAL 1
Divergence Angle VerticalDivergence 45575 B207 SRATIONAL 1
Horizontal Axis Distance AxisDistance_X 45576 B208 SRATIONAL 1
Vertical Axis Distance AxisDistance_Y 45577 B209 SRATIONAL 1
Collimation Axis Distance AxisDistance_Z 45578 B20A SRATIONAL 1
Yaw Angle YawAngle 45579 B20B SRATIONAL 1
Pitch Angle PitchAngle 45580 B20C SRATIONAL 1
Roll Angle RollAngle 45581 B20D SRATIONAL 1
*/
default:
break;
}
Expand All @@ -298,66 +292,70 @@ MPOData *jpeg_get_mpo_data(const guchar *data, guint size)
{
guint seg_offset;
guint seg_size;
if (jpeg_segment_find(data, size, JPEG_MARKER_APP2, "MPF\x00", 4, &seg_offset, &seg_size) && seg_size >16)
{
guint offset;
guint next_offset = 0;
TiffByteOrder bo;
MPOData *mpo;
guint i;
if (!jpeg_segment_find(data, size, JPEG_MARKER_APP2, "MPF\x00", 4, &seg_offset, &seg_size) || seg_size <= 16) return nullptr;

DEBUG_1("mpo signature found at %x", seg_offset);
seg_offset += 4;
seg_size -= 4;
DEBUG_1("mpo signature found at %x", seg_offset);
seg_offset += 4;
seg_size -= 4;

if (!tiff_directory_offset(data + seg_offset, seg_size, &offset, &bo)) return nullptr;
guint offset;
TiffByteOrder bo;
if (!tiff_directory_offset(data + seg_offset, seg_size, offset, bo)) return nullptr;

mpo = g_new0(MPOData, 1);
mpo->mpo_offset = seg_offset;
auto *mpo = g_new0(MPOData, 1);
mpo->mpo_offset = seg_offset;

tiff_parse_IFD_table(data + seg_offset, offset , seg_size, bo, &next_offset, mpo_parse_Index_IFD_entry, mpo);
if (!mpo->images) mpo->num_images = 0;
guint next_offset = 0;
const auto parse_mpo_data = [seg_size, mpo](const guchar *tiff, guint offset, TiffByteOrder bo)
{
return mpo_parse_Index_IFD_entry(tiff, offset, seg_size, bo, *mpo);
};
tiff_parse_IFD_table(data + seg_offset, offset, seg_size, bo, parse_mpo_data, &next_offset);

if (!mpo->images) mpo->num_images = 0;

for (i = 0; i < mpo->num_images; i++)
for (guint i = 0; i < mpo->num_images; i++)
{
if (mpo->images[i].offset + mpo->images[i].length > size)
{
if (mpo->images[i].offset + mpo->images[i].length > size)
{
mpo->num_images = i;
DEBUG_1("MPO file truncated to %u valid images, %u %u", i, mpo->images[i].offset + mpo->images[i].length, size);
break;
}
mpo->num_images = i;
DEBUG_1("MPO file truncated to %u valid images, %u %u", i, mpo->images[i].offset + mpo->images[i].length, size);
break;
}
}

for (i = 0; i < mpo->num_images; i++)
for (guint i = 0; i < mpo->num_images; i++)
{
if (i == 0)
{
if (i == 0)
offset = next_offset;
}
else
{
if (!jpeg_segment_find(data + mpo->images[i].offset, mpo->images[i].length, JPEG_MARKER_APP2, "MPF\x00", 4, &seg_offset, &seg_size) || seg_size <=16)
{
offset = next_offset;
DEBUG_1("MPO image %u: MPO signature not found", i);
continue;
}
else
{
if (!jpeg_segment_find(data + mpo->images[i].offset, mpo->images[i].length, JPEG_MARKER_APP2, "MPF\x00", 4, &seg_offset, &seg_size) || seg_size <=16)
{
DEBUG_1("MPO image %u: MPO signature not found", i);
continue;
}

seg_offset += 4;
seg_size -= 4;
if (!tiff_directory_offset(data + mpo->images[i].offset + seg_offset, seg_size, &offset, &bo))
{
DEBUG_1("MPO image %u: invalid directory offset", i);
continue;
}

seg_offset += 4;
seg_size -= 4;
if (!tiff_directory_offset(data + mpo->images[i].offset + seg_offset, seg_size, offset, bo))
{
DEBUG_1("MPO image %u: invalid directory offset", i);
continue;
}
tiff_parse_IFD_table(data + mpo->images[i].offset + seg_offset, offset , seg_size, bo, nullptr, mpo_parse_Attributes_IFD_entry, &mpo->images[i]);

}

return mpo;
const auto parse_mpo_entry = [&mpe = mpo->images[i]](const guchar *tiff, guint offset, TiffByteOrder bo)
{
return mpo_parse_Attributes_IFD_entry(tiff, offset, bo, mpe);
};
tiff_parse_IFD_table(data + mpo->images[i].offset + seg_offset, offset, seg_size, bo, parse_mpo_entry);
}
return nullptr;

return mpo;
}

void jpeg_mpo_data_free(MPOData *mpo)
Expand Down
24 changes: 12 additions & 12 deletions src/jpeg-parser.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -62,18 +62,18 @@ struct MPOEntry {
guint MPFVersion;
guint MPIndividualNum;
guint PanOrientation;
double PanOverlap_H;
double PanOverlap_V;
guint BaseViewpointNum;
double ConvergenceAngle;
double BaselineLength;
double VerticalDivergence;
double AxisDistance_X;
double AxisDistance_Y;
double AxisDistance_Z;
double YawAngle;
double PitchAngle;
double RollAngle;
// double PanOverlap_H;
// double PanOverlap_V;
// guint BaseViewpointNum;
// double ConvergenceAngle;
// double BaselineLength;
// double VerticalDivergence;
// double AxisDistance_X;
// double AxisDistance_Y;
// double AxisDistance_Z;
// double YawAngle;
// double PitchAngle;
// double RollAngle;
};


Expand Down

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