diff options
Diffstat (limited to 'imgutils.py')
| -rw-r--r-- | imgutils.py | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/imgutils.py b/imgutils.py new file mode 100644 index 0000000..955cf8f --- /dev/null +++ b/imgutils.py @@ -0,0 +1,230 @@ +import os +import shutil +import subprocess +from io import BytesIO +from tempfile import NamedTemporaryFile + +from PIL import Image, ImageOps + +from config import IMAGE_STRIP_HEIGHT, IMAGE_QUALITY, IMAGE_CACHE, IMAGE_MAX_WIDTH, THUMBNAIL_WIDTH, THUMBNAIL_HEIGHT, \ + THUMBNAIL_QUALITY + +Image.MAX_IMAGE_PIXELS = 1000000000 +from glob import glob + +def _copy(src, dst): + try: + os.link(src, dst) + except: + shutil.copy(src, dst) + + +def rechunk(im): + + height = im.height + width = im.width + last_chunk = (height // IMAGE_STRIP_HEIGHT) - 1 + + for i, cursor in enumerate(range(0, height, IMAGE_STRIP_HEIGHT)): + + if i == last_chunk: + chunk_height = IMAGE_STRIP_HEIGHT + (height % IMAGE_STRIP_HEIGHT) + else: + chunk_height = min(IMAGE_STRIP_HEIGHT, height) + + yield im.crop((0, cursor, width, cursor + chunk_height)) + + if i == last_chunk: + break + +def webp_convert(input_file, output_file, quality=IMAGE_QUALITY): + + subprocess.run([ + "ffmpeg", "-y", "-loglevel", "error", "-hide_banner", "-nostats", "-i", input_file, + "-c:v", "libwebp", "-preset", "drawing", "-quality", str(quality), "-compression_level", "6", + output_file + ], text=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL, check=True) + +def copy_from_cache(cache_folder, output_folder): + + for filename in glob(os.path.join(cache_folder, "*.webp")): + _copy(filename, os.path.join(output_folder, os.path.basename(filename))) + +def is_cached(cache_folder): + if os.path.exists(os.path.join(cache_folder, "ok")): + return True + + return False + +def convert_cover(cache_key, filename, output_folder): + cache_folder = os.path.join(IMAGE_CACHE, cache_key) + + os.makedirs(output_folder, exist_ok=True) + output_filename = os.path.join(output_folder, "cover.webp") + if os.path.exists(output_filename): + os.remove(output_filename) + + if is_cached(cache_folder): + copy_from_cache(cache_folder, output_folder) + return + + shutil.rmtree(cache_folder, ignore_errors=True) + os.makedirs(cache_folder) + + im = open_image(filename) + + if im.width > IMAGE_MAX_WIDTH: + aspect_ratio = im.height / im.width + new_height = int(IMAGE_MAX_WIDTH * aspect_ratio) + + im = im.resize((IMAGE_MAX_WIDTH, new_height), resample=Image.Resampling.LANCZOS) + + if im.mode != "RGB": + im = im.convert("RGB") + + try: + with NamedTemporaryFile(delete=False, suffix=".png") as f: + im.save(f) + + webp_convert(f.name, os.path.join(cache_folder, f"cover.webp"), quality=90) + + finally: + os.remove(f.name) + + with open(os.path.join(cache_folder, "ok"), "w"): + pass + + copy_from_cache(cache_folder, output_folder) + +def convert_rgb(im): + if im.mode == "RGBA": + background = Image.new('RGBA', im.size, color=(0, 0, 0)) + alpha_composite = Image.alpha_composite(background, im) + im = alpha_composite.convert("RGB") + + if im.mode != "RGB": + im = im.convert("RGB") + + return im + +def convert_rgba(im): + if im.mode != "RGBA": + im = im.convert("RGBA") + + return im + + +def convert_chapter(cache_key, images, output_folder): + + # TODO: for non-long strips, stack horizontally + # Limit height to + + cache_folder = os.path.join(IMAGE_CACHE, cache_key) + + shutil.rmtree(output_folder, ignore_errors=True) + os.makedirs(output_folder) + + if is_cached(cache_folder): + copy_from_cache(cache_folder, output_folder) + return + + shutil.rmtree(cache_folder, ignore_errors=True) + os.makedirs(cache_folder) + + resized = [] + + # Resize images + for filename in images: + im = open_image(filename) + + im = convert_rgb(im) + + if im.width > IMAGE_MAX_WIDTH: + + aspect_ratio = im.height / im.width + new_height = int(IMAGE_MAX_WIDTH * aspect_ratio) + + if new_height == 0: + continue + + im = im.resize((IMAGE_MAX_WIDTH, new_height), resample=Image.Resampling.LANCZOS) + + resized.append(im) + + # Prepare canvases + canvases = [ + [resized[0]] + ] + current_canvas = canvases[0] + last_image_width = resized[0].width + for i in range(1, len(resized)): + + if last_image_width != resized[i].width: + canvases.append([]) + current_canvas = canvases[-1] + + current_canvas.append(resized[i]) + last_image_width = resized[i].width + + # Stack + stacked_images = [] + for canvas in canvases: + width = canvas[0].width + height = sum(im.height for im in canvas) + + new_image = Image.new("RGB", (width, height), color=(0, 0, 0, 0)) + + cursor = 0 + for img in canvas: + new_image.paste(img, (0, cursor)) + cursor += img.height + + stacked_images.append(new_image) + + # Rechunk + chunks = [] + for im in stacked_images: + for im_chunk in rechunk(im): + chunks.append(im_chunk) + + # Convert + for i, chunk in enumerate(chunks): + + try: + with NamedTemporaryFile(delete=False, suffix=".png") as f: + chunk.save(f) + + webp_convert(f.name, os.path.join(cache_folder, f"{i:03d}.webp")) + + finally: + os.remove(f.name) + + with open(os.path.join(cache_folder, "ok"), "w"): + pass + + copy_from_cache(cache_folder, output_folder) + +def open_image(filename): + + with open(filename, "rb") as f: + data = f.read() + + io = BytesIO(data) + io.name = filename + return Image.open(io) + +def create_thumbnail_sheet(images, output_filename): + images = [open_image(image["cover"]) for image in images] + + width = len(images) * THUMBNAIL_WIDTH + height = THUMBNAIL_HEIGHT + + new_image = Image.new("RGBA", (width, height), color=(0, 0, 0, 0)) + + for i, im in enumerate(images): + im = convert_rgba(im) + + im = ImageOps.pad(im, (THUMBNAIL_WIDTH, THUMBNAIL_HEIGHT), color=(0, 0, 0, 0), method=Image.Resampling.LANCZOS) + new_image.paste(im, (i * THUMBNAIL_WIDTH, 0)) + + new_image.save(output_filename, quality=THUMBNAIL_QUALITY) |