#!/usr/bin/env python3
"""
Generate test EPUBs for image rendering verification.
Creates EPUBs with annotated JPEG and PNG images to verify:
- Grayscale rendering (4 levels)
- Image scaling
- Image centering
- Cache performance
- Page serialization
"""
import os
import zipfile
from pathlib import Path
try:
from PIL import Image, ImageDraw, ImageFont
except ImportError:
print("Please install Pillow: pip install Pillow")
exit(1)
OUTPUT_DIR = Path(__file__).parent.parent / "test" / "epubs"
SCREEN_WIDTH = 480
SCREEN_HEIGHT = 800
def get_font(size=20):
"""Get a font, falling back to default if needed."""
try:
return ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf", size)
except:
try:
return ImageFont.truetype("/usr/share/fonts/TTF/DejaVuSans.ttf", size)
except:
return ImageFont.load_default()
def draw_text_centered(draw, y, text, font, fill=0):
"""Draw centered text at given y position."""
bbox = draw.textbbox((0, 0), text, font=font)
text_width = bbox[2] - bbox[0]
x = (draw.im.size[0] - text_width) // 2
draw.text((x, y), text, font=font, fill=fill)
def draw_text_wrapped(draw, x, y, text, font, max_width, fill=0):
"""Draw text with word wrapping."""
words = text.split()
lines = []
current_line = []
for word in words:
test_line = ' '.join(current_line + [word])
bbox = draw.textbbox((0, 0), test_line, font=font)
if bbox[2] - bbox[0] <= max_width:
current_line.append(word)
else:
if current_line:
lines.append(' '.join(current_line))
current_line = [word]
if current_line:
lines.append(' '.join(current_line))
line_height = font.size + 4 if hasattr(font, 'size') else 20
for i, line in enumerate(lines):
draw.text((x, y + i * line_height), line, font=font, fill=fill)
return len(lines) * line_height
def create_grayscale_test_image(filename, is_png=True):
"""
Create image with 4 grayscale squares to verify 4-level rendering.
"""
width, height = 400, 600
img = Image.new('L', (width, height), 255)
draw = ImageDraw.Draw(img)
font = get_font(16)
font_small = get_font(14)
# Title
draw_text_centered(draw, 10, "GRAYSCALE TEST", font, fill=0)
draw_text_centered(draw, 35, "Verify 4 distinct gray levels", font_small, fill=64)
# Draw 4 grayscale squares
square_size = 70
start_y = 65
gap = 10
# Gray levels chosen to avoid Bayer dithering threshold boundaries (±40 dither offset)
# Thresholds at 64, 128, 192 - use values in the middle of each band for solid output
# Safe zones: 0-23 (black), 88-103 (dark gray), 152-167 (light gray), 232-255 (white)
levels = [
(0, "Level 0: BLACK"),
(96, "Level 1: DARK GRAY"),
(160, "Level 2: LIGHT GRAY"),
(255, "Level 3: WHITE"),
]
for i, (gray_value, label) in enumerate(levels):
y = start_y + i * (square_size + gap + 22)
x = (width - square_size) // 2
# Draw square with border
draw.rectangle([x-2, y-2, x + square_size + 2, y + square_size + 2], fill=0)
draw.rectangle([x, y, x + square_size, y + square_size], fill=gray_value)
# Label below square
bbox = draw.textbbox((0, 0), label, font=font_small)
label_width = bbox[2] - bbox[0]
draw.text(((width - label_width) // 2, y + square_size + 5), label, font=font_small, fill=0)
# Instructions at bottom (well below the last square)
y = height - 70
draw_text_centered(draw, y, "PASS: 4 distinct shades visible", font_small, fill=0)
draw_text_centered(draw, y + 20, "FAIL: Only black/white or", font_small, fill=64)
draw_text_centered(draw, y + 38, "muddy/indistinct grays", font_small, fill=64)
# Save
if is_png:
img.save(filename, 'PNG')
else:
img.save(filename, 'JPEG', quality=95)
def create_centering_test_image(filename, is_png=True):
"""
Create image with border markers to verify centering.
"""
width, height = 350, 400
img = Image.new('L', (width, height), 255)
draw = ImageDraw.Draw(img)
font = get_font(16)
font_small = get_font(14)
# Draw border
draw.rectangle([0, 0, width-1, height-1], outline=0, width=3)
# Corner markers
marker_size = 20
for x, y in [(0, 0), (width-marker_size, 0), (0, height-marker_size), (width-marker_size, height-marker_size)]:
draw.rectangle([x, y, x+marker_size, y+marker_size], fill=0)
# Center cross
cx, cy = width // 2, height // 2
draw.line([cx - 30, cy, cx + 30, cy], fill=0, width=2)
draw.line([cx, cy - 30, cx, cy + 30], fill=0, width=2)
# Title
draw_text_centered(draw, 40, "CENTERING TEST", font, fill=0)
# Instructions
y = 80
draw_text_centered(draw, y, "Image should be centered", font_small, fill=0)
draw_text_centered(draw, y + 20, "horizontally on screen", font_small, fill=0)
y = 150
draw_text_centered(draw, y, "Check:", font_small, fill=0)
draw_text_centered(draw, y + 25, "- Equal margins left & right", font_small, fill=64)
draw_text_centered(draw, y + 45, "- All 4 corners visible", font_small, fill=64)
draw_text_centered(draw, y + 65, "- Border is complete rectangle", font_small, fill=64)
# Pass/fail
y = height - 80
draw_text_centered(draw, y, "PASS: Centered, all corners visible", font_small, fill=0)
draw_text_centered(draw, y + 20, "FAIL: Off-center or cropped", font_small, fill=64)
if is_png:
img.save(filename, 'PNG')
else:
img.save(filename, 'JPEG', quality=95)
def create_scaling_test_image(filename, is_png=True):
"""
Create large image to verify scaling works.
"""
# Make image larger than screen but within decoder limits (max 2048x1536)
width, height = 1200, 1500
img = Image.new('L', (width, height), 240)
draw = ImageDraw.Draw(img)
font = get_font(48)
font_medium = get_font(32)
font_small = get_font(24)
# Border
draw.rectangle([0, 0, width-1, height-1], outline=0, width=8)
draw.rectangle([20, 20, width-21, height-21], outline=128, width=4)
# Title
draw_text_centered(draw, 60, "SCALING TEST", font, fill=0)
draw_text_centered(draw, 130, f"Original: {width}x{height} (larger than screen)", font_medium, fill=64)
# Grid pattern to verify scaling quality
grid_start_y = 220
grid_size = 400
cell_size = 50
draw_text_centered(draw, grid_start_y - 40, "Grid pattern (check for artifacts):", font_small, fill=0)
grid_x = (width - grid_size) // 2
for row in range(grid_size // cell_size):
for col in range(grid_size // cell_size):
x = grid_x + col * cell_size
y = grid_start_y + row * cell_size
if (row + col) % 2 == 0:
draw.rectangle([x, y, x + cell_size, y + cell_size], fill=0)
else:
draw.rectangle([x, y, x + cell_size, y + cell_size], fill=200)
# Size indicator bars
y = grid_start_y + grid_size + 60
draw_text_centered(draw, y, "Width markers (should fit on screen):", font_small, fill=0)
bar_y = y + 40
# Full width bar
draw.rectangle([50, bar_y, width - 50, bar_y + 30], fill=0)
draw.text((60, bar_y + 5), "FULL WIDTH", font=font_small, fill=255)
# Half width bar
bar_y += 60
half_start = width // 4
draw.rectangle([half_start, bar_y, width - half_start, bar_y + 30], fill=85)
draw.text((half_start + 10, bar_y + 5), "HALF WIDTH", font=font_small, fill=255)
# Instructions
y = height - 350
draw_text_centered(draw, y, "VERIFICATION:", font_medium, fill=0)
y += 50
instructions = [
"1. Image fits within screen bounds",
"2. All borders visible (not cropped)",
"3. Grid pattern clear (no moire)",
"4. Text readable after scaling",
"5. Aspect ratio preserved (not stretched)",
]
for i, text in enumerate(instructions):
draw_text_centered(draw, y + i * 35, text, font_small, fill=64)
y = height - 100
draw_text_centered(draw, y, "PASS: Scaled down, readable, complete", font_small, fill=0)
draw_text_centered(draw, y + 30, "FAIL: Cropped, distorted, or unreadable", font_small, fill=64)
if is_png:
img.save(filename, 'PNG')
else:
img.save(filename, 'JPEG', quality=95)
def create_wide_scaling_test_image(filename, is_png=True):
"""
Create wide image (1807x736) to test scaling with specific dimensions
that can trigger cache dimension mismatches due to floating-point rounding.
"""
width, height = 1807, 736
img = Image.new('L', (width, height), 240)
draw = ImageDraw.Draw(img)
font = get_font(48)
font_medium = get_font(32)
font_small = get_font(24)
# Border
draw.rectangle([0, 0, width-1, height-1], outline=0, width=6)
draw.rectangle([15, 15, width-16, height-16], outline=128, width=3)
# Title
draw_text_centered(draw, 40, "WIDE SCALING TEST", font, fill=0)
draw_text_centered(draw, 100, f"Original: {width}x{height} (tests rounding edge case)", font_medium, fill=64)
# Grid pattern to verify scaling quality
grid_start_x = 100
grid_start_y = 180
grid_width = 600
grid_height = 300
cell_size = 50
draw.text((grid_start_x, grid_start_y - 35), "Grid pattern (check for artifacts):", font=font_small, fill=0)
for row in range(grid_height // cell_size):
for col in range(grid_width // cell_size):
x = grid_start_x + col * cell_size
y = grid_start_y + row * cell_size
if (row + col) % 2 == 0:
draw.rectangle([x, y, x + cell_size, y + cell_size], fill=0)
else:
draw.rectangle([x, y, x + cell_size, y + cell_size], fill=200)
# Verification section on the right
text_x = 800
text_y = 180
draw.text((text_x, text_y), "VERIFICATION:", font=font_medium, fill=0)
text_y += 50
instructions = [
"1. Image fits within screen",
"2. All borders visible",
"3. Grid pattern clear",
"4. Text readable",
"5. No double-decode in log",
]
for i, text in enumerate(instructions):
draw.text((text_x, text_y + i * 35), text, font=font_small, fill=64)
# Dimension info
draw.text((text_x, 450), f"Dimensions: {width}x{height}", font=font_small, fill=0)
draw.text((text_x, 485), "Tests cache dimension matching", font=font_small, fill=64)
# Pass/fail at bottom
y = height - 80
draw_text_centered(draw, y, "PASS: Single decode, cached correctly", font_small, fill=0)
draw_text_centered(draw, y + 30, "FAIL: Cache mismatch, multiple decodes", font_small, fill=64)
if is_png:
img.save(filename, 'PNG')
else:
img.save(filename, 'JPEG', quality=95)
def create_cache_test_image(filename, page_num, is_png=True):
"""
Create image for cache performance testing.
"""
width, height = 400, 300
img = Image.new('L', (width, height), 255)
draw = ImageDraw.Draw(img)
font = get_font(18)
font_small = get_font(14)
font_large = get_font(36)
# Border
draw.rectangle([0, 0, width-1, height-1], outline=0, width=2)
# Page number prominent
draw_text_centered(draw, 30, f"CACHE TEST PAGE {page_num}", font, fill=0)
draw_text_centered(draw, 80, f"#{page_num}", font_large, fill=0)
# Instructions
y = 140
draw_text_centered(draw, y, "Navigate away then return", font_small, fill=64)
draw_text_centered(draw, y + 25, "Second load should be faster", font_small, fill=64)
y = 220
draw_text_centered(draw, y, "PASS: Faster reload from cache", font_small, fill=0)
draw_text_centered(draw, y + 20, "FAIL: Same slow decode each time", font_small, fill=64)
if is_png:
img.save(filename, 'PNG')
else:
img.save(filename, 'JPEG', quality=95)
def create_gradient_test_image(filename, is_png=True):
"""
Create horizontal gradient to test grayscale banding.
"""
width, height = 400, 500
img = Image.new('L', (width, height), 255)
draw = ImageDraw.Draw(img)
font = get_font(16)
font_small = get_font(14)
draw_text_centered(draw, 10, "GRADIENT TEST", font, fill=0)
draw_text_centered(draw, 35, "Smooth gradient → 4 bands expected", font_small, fill=64)
# Horizontal gradient
gradient_y = 70
gradient_height = 100
for x in range(width):
gray = int(255 * x / width)
draw.line([(x, gradient_y), (x, gradient_y + gradient_height)], fill=gray)
# Border around gradient
draw.rectangle([0, gradient_y-1, width-1, gradient_y + gradient_height + 1], outline=0, width=1)
# Labels
y = gradient_y + gradient_height + 10
draw.text((5, y), "BLACK", font=font_small, fill=0)
draw.text((width - 50, y), "WHITE", font=font_small, fill=0)
# 4-step gradient (what it should look like)
y = 220
draw_text_centered(draw, y, "Expected result (4 distinct bands):", font_small, fill=0)
band_y = y + 25
band_height = 60
band_width = width // 4
for i, gray in enumerate([0, 85, 170, 255]):
x = i * band_width
draw.rectangle([x, band_y, x + band_width, band_y + band_height], fill=gray)
draw.rectangle([0, band_y-1, width-1, band_y + band_height + 1], outline=0, width=1)
# Vertical gradient
y = 340
draw_text_centered(draw, y, "Vertical gradient:", font_small, fill=0)
vgrad_y = y + 25
vgrad_height = 80
for row in range(vgrad_height):
gray = int(255 * row / vgrad_height)
draw.line([(50, vgrad_y + row), (width - 50, vgrad_y + row)], fill=gray)
draw.rectangle([49, vgrad_y-1, width-49, vgrad_y + vgrad_height + 1], outline=0, width=1)
# Pass/fail
y = height - 50
draw_text_centered(draw, y, "PASS: Clear 4-band quantization", font_small, fill=0)
draw_text_centered(draw, y + 20, "FAIL: Binary/noisy dithering", font_small, fill=64)
if is_png:
img.save(filename, 'PNG')
else:
img.save(filename, 'JPEG', quality=95)
def create_format_test_image(filename, format_name, is_png=True):
"""
Create simple image to verify format support.
"""
width, height = 350, 250
img = Image.new('L', (width, height), 255)
draw = ImageDraw.Draw(img)
font = get_font(20)
font_large = get_font(36)
font_small = get_font(14)
# Border
draw.rectangle([0, 0, width-1, height-1], outline=0, width=3)
# Format name
draw_text_centered(draw, 30, f"{format_name} FORMAT TEST", font, fill=0)
draw_text_centered(draw, 80, format_name, font_large, fill=0)
# Checkmark area
y = 140
draw_text_centered(draw, y, "If you can read this,", font_small, fill=64)
draw_text_centered(draw, y + 20, f"{format_name} decoding works!", font_small, fill=64)
y = height - 40
draw_text_centered(draw, y, f"PASS: {format_name} image visible", font_small, fill=0)
if is_png:
img.save(filename, 'PNG')
else:
img.save(filename, 'JPEG', quality=95)
def create_epub(epub_path, title, chapters):
"""
Create an EPUB file with the given chapters.
chapters: list of (chapter_title, html_content, images)
images: list of (image_filename, image_data)
"""
with zipfile.ZipFile(epub_path, 'w', zipfile.ZIP_DEFLATED) as epub:
# mimetype (must be first, uncompressed)
epub.writestr('mimetype', 'application/epub+zip', compress_type=zipfile.ZIP_STORED)
# Container
container_xml = '''
This EPUB tests JPEG image rendering.
Navigate through chapters to verify each test case.
Test Plan:
Basic JPEG decoding test.
If the image above is visible, JPEG decoding works.
"""), [('jpeg_format.jpg', images['jpeg_format.jpg'])]), ("2. Grayscale", make_chapter("Grayscale Test", """Verify 4 distinct gray levels are visible.
"""), [('grayscale_test.jpg', images['grayscale_test.jpg'])]),
("3. Gradient", make_chapter("Gradient Test", """
Verify gradient quantizes to 4 bands.
"""), [('gradient_test.jpg', images['gradient_test.jpg'])]),
("4. Centering", make_chapter("Centering Test", """
Verify image is centered horizontally.
"""), [('centering_test.jpg', images['centering_test.jpg'])]),
("5. Scaling", make_chapter("Scaling Test", """
This image is 1200x1500 pixels - larger than the screen.
It should be scaled down to fit.
"""), [('scaling_test.jpg', images['scaling_test.jpg'])]),
("6. Wide Scaling", make_chapter("Wide Scaling Test", """
This image is 1807x736 pixels - a wide landscape format.
Tests scaling with dimensions that can cause cache mismatches.
"""), [('wide_scaling_test.jpg', images['wide_scaling_test.jpg'])]),
("7. Cache Test A", make_chapter("Cache Test - Page A", """
First cache test page. Note the load time.
Navigate to next page, then come back.
"""), [('cache_test_1.jpg', images['cache_test_1.jpg'])]), ("8. Cache Test B", make_chapter("Cache Test - Page B", """Second cache test page.
Navigate back to Page A - it should load faster from cache.
"""), [('cache_test_2.jpg', images['cache_test_2.jpg'])]), ("9. Alignment Bleed", make_chapter("Image Centering Bleed Test", """Tests that image centering does not bleed into following text blocks (issue #1026).
Set Paragraph Alignment to Justify and Embedded Style to OFF before testing.
All paragraphs below the images should be justified, not centered.

FIRST PARAGRAPH after image. This paragraph follows an empty heading and an image-only paragraph. With the bug present, this text appears centered instead of justified because the empty heading's default Center alignment bleeds through the chain of empty text blocks. Lorem ipsum dolor sit amet, consectetur adipiscing elit sed do eiusmod tempor.
SECOND PARAGRAPH in the same div. This paragraph should always be justified because the first paragraph's text block was flushed. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident sunt in culpa qui officia.
This EPUB tests PNG image rendering.
Navigate through chapters to verify each test case.
Test Plan:
Basic PNG decoding test.
If the image above is visible and no crash occurred, PNG decoding works.
"""), [('png_format.png', images['png_format.png'])]), ("2. Grayscale", make_chapter("Grayscale Test", """Verify 4 distinct gray levels are visible.
"""), [('grayscale_test.png', images['grayscale_test.png'])]),
("3. Gradient", make_chapter("Gradient Test", """
Verify gradient quantizes to 4 bands.
"""), [('gradient_test.png', images['gradient_test.png'])]),
("4. Centering", make_chapter("Centering Test", """
Verify image is centered horizontally.
"""), [('centering_test.png', images['centering_test.png'])]),
("5. Scaling", make_chapter("Scaling Test", """
This image is 1200x1500 pixels - larger than the screen.
It should be scaled down to fit.
"""), [('scaling_test.png', images['scaling_test.png'])]),
("6. Wide Scaling", make_chapter("Wide Scaling Test", """
This image is 1807x736 pixels - a wide landscape format.
Tests scaling with dimensions that can cause cache mismatches.
"""), [('wide_scaling_test.png', images['wide_scaling_test.png'])]),
("7. Cache Test A", make_chapter("Cache Test - Page A", """
First cache test page. Note the load time.
Navigate to next page, then come back.
"""), [('cache_test_1.png', images['cache_test_1.png'])]), ("8. Cache Test B", make_chapter("Cache Test - Page B", """Second cache test page.
Navigate back to Page A - it should load faster from cache.
"""), [('cache_test_2.png', images['cache_test_2.png'])]), ("9. Alignment Bleed", make_chapter("Image Centering Bleed Test", """Tests that image centering does not bleed into following text blocks (issue #1026).
Set Paragraph Alignment to Justify and Embedded Style to OFF before testing.
All paragraphs below the images should be justified, not centered.

FIRST PARAGRAPH after image. This paragraph follows an empty heading and an image-only paragraph. With the bug present, this text appears centered instead of justified because the empty heading's default Center alignment bleeds through the chain of empty text blocks. Lorem ipsum dolor sit amet, consectetur adipiscing elit sed do eiusmod tempor.
SECOND PARAGRAPH in the same div. This paragraph should always be justified because the first paragraph's text block was flushed. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident sunt in culpa qui officia.
This EPUB contains both JPEG and PNG images.
Tests format detection and mixed rendering.
"""), []), ("1. JPEG Image", make_chapter("JPEG in Mixed EPUB", """This is a JPEG image:
"""), [('jpeg_format.jpg', images['jpeg_format.jpg'])]),
("2. PNG Image", make_chapter("PNG in Mixed EPUB", """
This is a PNG image:
"""), [('png_format.png', images['png_format.png'])]),
("3. Both Formats", make_chapter("Both Formats on One Page", """
JPEG image:
PNG image:
Both should render with proper grayscale.
"""), [('grayscale_test.jpg', images['grayscale_test.jpg']), ('grayscale_test.png', images['grayscale_test.png'])]), ] create_epub(OUTPUT_DIR / 'test_mixed_images.epub', 'Mixed Format Tests', mixed_chapters) print(f"\nTest EPUBs created in: {OUTPUT_DIR}") print("Files:") for f in OUTPUT_DIR.glob('*.epub'): print(f" - {f.name}") if __name__ == '__main__': main()