Add basic support for adding SVG pictures to docx files

See issues python-openxml#351, python-openxml#651, python-openxml#659.

(cherry picked from commit 8f54818)

docx/image/__init__.py

@@ -0,0 +1,31 @@
+# encoding: utf-8
+
+"""
+Provides objects that can characterize image streams as to content type and
+size, as a required step in including them in a document.
+"""
+
+from __future__ import (
+    absolute_import, division, print_function, unicode_literals
+)
+
+from docx.image.bmp import Bmp
+from docx.image.gif import Gif
+from docx.image.jpeg import Exif, Jfif
+from docx.image.png import Png
+from docx.image.tiff import Tiff
+from docx.image.svg import Svg
+
+
+SIGNATURES = (
+    # class, offset, signature_bytes
+    (Png,  0, b'\x89PNG\x0D\x0A\x1A\x0A'),
+    (Jfif, 6, b'JFIF'),
+    (Exif, 6, b'Exif'),
+    (Gif,  0, b'GIF87a'),
+    (Gif,  0, b'GIF89a'),
+    (Tiff, 0, b'MM\x00*'),  # big-endian (Motorola) TIFF
+    (Tiff, 0, b'II*\x00'),  # little-endian (Intel) TIFF
+    (Bmp,  0, b'BM'),
+    (Svg,  0, b'<svg '),
+)

docx/image/constants.py

@@ -0,0 +1,170 @@
+# encoding: utf-8
+
+"""
+Constants specific the the image sub-package
+"""
+
+
+class JPEG_MARKER_CODE(object):
+    """
+    JPEG marker codes
+    """
+    TEM = b'\x01'
+    DHT = b'\xC4'
+    DAC = b'\xCC'
+    JPG = b'\xC8'
+
+    SOF0 = b'\xC0'
+    SOF1 = b'\xC1'
+    SOF2 = b'\xC2'
+    SOF3 = b'\xC3'
+    SOF5 = b'\xC5'
+    SOF6 = b'\xC6'
+    SOF7 = b'\xC7'
+    SOF9 = b'\xC9'
+    SOFA = b'\xCA'
+    SOFB = b'\xCB'
+    SOFD = b'\xCD'
+    SOFE = b'\xCE'
+    SOFF = b'\xCF'
+
+    RST0 = b'\xD0'
+    RST1 = b'\xD1'
+    RST2 = b'\xD2'
+    RST3 = b'\xD3'
+    RST4 = b'\xD4'
+    RST5 = b'\xD5'
+    RST6 = b'\xD6'
+    RST7 = b'\xD7'
+
+    SOI = b'\xD8'
+    EOI = b'\xD9'
+    SOS = b'\xDA'
+    DQT = b'\xDB'  # Define Quantization Table(s)
+    DNL = b'\xDC'
+    DRI = b'\xDD'
+    DHP = b'\xDE'
+    EXP = b'\xDF'
+
+    APP0 = b'\xE0'
+    APP1 = b'\xE1'
+    APP2 = b'\xE2'
+    APP3 = b'\xE3'
+    APP4 = b'\xE4'
+    APP5 = b'\xE5'
+    APP6 = b'\xE6'
+    APP7 = b'\xE7'
+    APP8 = b'\xE8'
+    APP9 = b'\xE9'
+    APPA = b'\xEA'
+    APPB = b'\xEB'
+    APPC = b'\xEC'
+    APPD = b'\xED'
+    APPE = b'\xEE'
+    APPF = b'\xEF'
+
+    STANDALONE_MARKERS = (
+        TEM, SOI, EOI, RST0, RST1, RST2, RST3, RST4, RST5, RST6, RST7
+    )
+
+    SOF_MARKER_CODES = (
+        SOF0, SOF1, SOF2, SOF3, SOF5, SOF6, SOF7, SOF9, SOFA, SOFB, SOFD,
+        SOFE, SOFF
+    )
+
+    marker_names = {
+        b'\x00': 'UNKNOWN',
+        b'\xC0': 'SOF0',
+        b'\xC2': 'SOF2',
+        b'\xC4': 'DHT',
+        b'\xDA': 'SOS',   # start of scan
+        b'\xD8': 'SOI',   # start of image
+        b'\xD9': 'EOI',   # end of image
+        b'\xDB': 'DQT',
+        b'\xE0': 'APP0',
+        b'\xE1': 'APP1',
+        b'\xE2': 'APP2',
+        b'\xED': 'APP13',
+        b'\xEE': 'APP14',
+    }
+
+    @classmethod
+    def is_standalone(cls, marker_code):
+        return marker_code in cls.STANDALONE_MARKERS
+
+
+class MIME_TYPE(object):
+    """
+    Image content types
+    """
+    BMP = 'image/bmp'
+    GIF = 'image/gif'
+    JPEG = 'image/jpeg'
+    PNG = 'image/png'
+    TIFF = 'image/tiff'
+    SVG = 'image/svg+xml'
+
+
+class PNG_CHUNK_TYPE(object):
+    """
+    PNG chunk type names
+    """
+    IHDR = 'IHDR'
+    pHYs = 'pHYs'
+    IEND = 'IEND'
+
+
+class TIFF_FLD_TYPE(object):
+    """
+    Tag codes for TIFF Image File Directory (IFD) entries.
+    """
+    BYTE = 1
+    ASCII = 2
+    SHORT = 3
+    LONG = 4
+    RATIONAL = 5
+
+    field_type_names = {
+        1: 'BYTE', 2: 'ASCII char', 3: 'SHORT', 4: 'LONG',
+        5: 'RATIONAL'
+    }
+
+
+TIFF_FLD = TIFF_FLD_TYPE
+
+
+class TIFF_TAG(object):
+    """
+    Tag codes for TIFF Image File Directory (IFD) entries.
+    """
+    IMAGE_WIDTH = 0x0100
+    IMAGE_LENGTH = 0x0101
+    X_RESOLUTION = 0x011A
+    Y_RESOLUTION = 0x011B
+    RESOLUTION_UNIT = 0x0128
+
+    tag_names = {
+        0x00FE: 'NewSubfileType',
+        0x0100: 'ImageWidth',
+        0x0101: 'ImageLength',
+        0x0102: 'BitsPerSample',
+        0x0103: 'Compression',
+        0x0106: 'PhotometricInterpretation',
+        0x010E: 'ImageDescription',
+        0x010F: 'Make',
+        0x0110: 'Model',
+        0x0111: 'StripOffsets',
+        0x0112: 'Orientation',
+        0x0115: 'SamplesPerPixel',
+        0x0117: 'StripByteCounts',
+        0x011A: 'XResolution',
+        0x011B: 'YResolution',
+        0x011C: 'PlanarConfiguration',
+        0x0128: 'ResolutionUnit',
+        0x0131: 'Software',
+        0x0132: 'DateTime',
+        0x0213: 'YCbCrPositioning',
+        0x8769: 'ExifTag',
+        0x8825: 'GPS IFD',
+        0xC4A5: 'PrintImageMatching',
+    }