添加 giftool

konabot/plugins/image_process/__init__.py

@@ -1,6 +1,12 @@
+import re
+from io import BytesIO
+
 from nonebot import on_message
 from nonebot.adapters import Bot
+from nonebot_plugin_alconna import (Alconna, Args, Image, Option, UniMessage,
+                                    on_alconna)
 
+from konabot.common.nb.exc import BotExceptionMessage
 from konabot.common.nb.extract_image import PIL_Image
 from konabot.common.nb.match_keyword import match_keyword
 from konabot.common.nb.reply_image import reply_image
@@ -11,3 +17,135 @@ cmd_black_white = on_message(rule=match_keyword("黑白"))
 @cmd_black_white.handle()
 async def _(img: PIL_Image, bot: Bot):
     await reply_image(cmd_black_white, bot, img.convert("LA"))
+
+
+def parse_timestamp(tx: str) -> float | None:
+    res = 0.0
+    for component in tx.split(":"):
+        res *= 60
+        if not re.match(r"^\d+(\.\d+)?$", component):
+            return
+        res += float(component)
+    return res
+
+
+cmd_giftool = on_alconna(Alconna(
+    "giftool",
+    Args["img", Image | None],
+    Option("--ss", Args["start_point", str]),
+    Option("--frames:v", Args["frame_count", int]),
+    Option("-t", Args["length", str]),
+    Option("-to", Args["end_point", str]),
+))
+
+
+@cmd_giftool.handle()
+async def _(
+    image: PIL_Image,
+    start_point: str | None = None,
+    frame_count: int | None = None,
+    length: str | None = None,
+    end_point: str | None = None,
+):
+    ss: None | float = None
+    if start_point:
+        ss = parse_timestamp(start_point)
+        if ss is None:
+            raise BotExceptionMessage("--ss 的格式不满足条件")
+
+    t: None | float = None
+    if length:
+        t = parse_timestamp(length)
+        if t is None:
+            raise BotExceptionMessage("-t 的格式不满足条件")
+
+    to: None | float = None
+    if end_point:
+        to = parse_timestamp(end_point)
+        if to is None:
+            raise BotExceptionMessage("-to 的格式不满足条件")
+
+    if to is not None and ss is not None and to <= ss:
+        raise BotExceptionMessage("错误：出点时间小于入点")
+    if frame_count is not None and frame_count <= 0:
+        raise BotExceptionMessage("错误：帧数量应该大于 0")
+
+    if not getattr(image, "is_animated", False):
+        raise BotExceptionMessage("错误：输入的不是动图（GIF）")
+    frames = []
+    durations = []
+    total_duration = 0.0
+
+    try:
+        for i in range(getattr(image, "n_frames")):
+            image.seek(i)
+            frames.append(image.copy())
+            duration = image.info.get("duration", 100)  # 单位：毫秒
+            durations.append(duration)
+            total_duration += duration / 1000.0  # 转为秒
+    except EOFError:
+        pass
+
+    if not frames:
+        raise BotExceptionMessage("错误：读取 GIF 帧失败")
+
+    def time_to_frame_index(target_time: float) -> int:
+        if target_time <= 0:
+            return 0
+        cum = 0.0
+        for idx, dur in enumerate(durations):
+            cum += dur / 1000.0
+            if cum >= target_time:
+                return min(idx, len(frames) - 1)
+        return len(frames) - 1
+    start_frame = 0
+    end_frame = len(frames) - 1
+    if ss is not None:
+        start_frame = time_to_frame_index(ss)
+    if to is not None:
+        end_frame = time_to_frame_index(to)
+        if end_frame < start_frame:
+            end_frame = start_frame
+    elif t is not None:
+        end_time = (ss or 0.0) + t
+        end_frame = time_to_frame_index(end_time)
+        if end_frame < start_frame:
+            end_frame = start_frame
+
+    start_frame = max(0, start_frame)
+    end_frame = min(len(frames) - 1, end_frame)
+    selected_frames = frames[start_frame : end_frame + 1]
+    selected_durations = durations[start_frame : end_frame + 1]
+
+    if frame_count is not None and frame_count > 0:
+        if frame_count >= len(selected_frames):
+            pass
+        else:
+            step = len(selected_frames) / frame_count
+            sampled_frames = []
+            sampled_durations = []
+            for i in range(frame_count):
+                idx = int(i * step)
+                sampled_frames.append(selected_frames[idx])
+                sampled_durations.append(
+                    sum(selected_durations) // len(selected_durations)
+                )
+            selected_frames = sampled_frames
+            selected_durations = sampled_durations
+
+    output_img = BytesIO()
+
+    if selected_frames:
+        selected_frames[0].save(
+            output_img,
+            format="GIF",
+            save_all=True,
+            append_images=selected_frames[1:],
+            duration=selected_durations,
+            loop=0,
+        )
+    else:
+        raise BotExceptionMessage("错误：没有可输出的帧")
+    output_img.seek(0)
+
+    await cmd_giftool.send(await UniMessage().image(raw=output_img).export())