Write the image *data*, of shape ``(height, width, 1)`` (grayscale) or ``(height, width, 3)`` (RGB), as pdf object *id* and with the soft mask (alpha channel) *smask*, which should be either None or a ``(height, width, 1)`` array.
(self, data, id, smask=None)
| 1649 | return png_data, bit_depth, palette |
| 1650 | |
| 1651 | def _writeImg(self, data, id, smask=None): |
| 1652 | """ |
| 1653 | Write the image *data*, of shape ``(height, width, 1)`` (grayscale) or |
| 1654 | ``(height, width, 3)`` (RGB), as pdf object *id* and with the soft mask |
| 1655 | (alpha channel) *smask*, which should be either None or a ``(height, |
| 1656 | width, 1)`` array. |
| 1657 | """ |
| 1658 | height, width, color_channels = data.shape |
| 1659 | obj = {'Type': Name('XObject'), |
| 1660 | 'Subtype': Name('Image'), |
| 1661 | 'Width': width, |
| 1662 | 'Height': height, |
| 1663 | 'ColorSpace': Name({1: 'DeviceGray', 3: 'DeviceRGB'}[color_channels]), |
| 1664 | 'BitsPerComponent': 8} |
| 1665 | if smask: |
| 1666 | obj['SMask'] = smask |
| 1667 | if mpl.rcParams['pdf.compression']: |
| 1668 | if data.shape[-1] == 1: |
| 1669 | data = data.squeeze(axis=-1) |
| 1670 | png = {'Predictor': 10, 'Colors': color_channels, 'Columns': width} |
| 1671 | img = Image.fromarray(data) |
| 1672 | img_colors = img.getcolors(maxcolors=256) |
| 1673 | if color_channels == 3 and img_colors is not None: |
| 1674 | # Convert to indexed color if there are 256 colors or fewer. This can |
| 1675 | # significantly reduce the file size. |
| 1676 | num_colors = len(img_colors) |
| 1677 | palette = np.array([comp for _, color in img_colors for comp in color], |
| 1678 | dtype=np.uint8) |
| 1679 | palette24 = ((palette[0::3].astype(np.uint32) << 16) | |
| 1680 | (palette[1::3].astype(np.uint32) << 8) | |
| 1681 | palette[2::3]) |
| 1682 | rgb24 = ((data[:, :, 0].astype(np.uint32) << 16) | |
| 1683 | (data[:, :, 1].astype(np.uint32) << 8) | |
| 1684 | data[:, :, 2]) |
| 1685 | indices = np.argsort(palette24).astype(np.uint8) |
| 1686 | rgb8 = indices[np.searchsorted(palette24, rgb24, sorter=indices)] |
| 1687 | img = Image.fromarray(rgb8).convert("P") |
| 1688 | img.putpalette(palette) |
| 1689 | png_data, bit_depth, palette = self._writePng(img) |
| 1690 | if bit_depth is None or palette is None: |
| 1691 | raise RuntimeError("invalid PNG header") |
| 1692 | palette = palette[:num_colors * 3] # Trim padding; remove for Pillow>=9 |
| 1693 | obj['ColorSpace'] = [Name('Indexed'), Name('DeviceRGB'), |
| 1694 | num_colors - 1, palette] |
| 1695 | obj['BitsPerComponent'] = bit_depth |
| 1696 | png['Colors'] = 1 |
| 1697 | png['BitsPerComponent'] = bit_depth |
| 1698 | else: |
| 1699 | png_data, _, _ = self._writePng(img) |
| 1700 | else: |
| 1701 | png = None |
| 1702 | self.beginStream( |
| 1703 | id, |
| 1704 | self.reserveObject('length of image stream'), |
| 1705 | obj, |
| 1706 | png=png |
| 1707 | ) |
| 1708 | if png: |
no test coverage detected