From 20c3db2f5f84666c6d4a7607a08a67145735e0f9 Mon Sep 17 00:00:00 2001
From: ERROR404 <32724548+hebtuerror404@users.noreply.github.com>
Date: Sun, 18 Dec 2022 22:02:28 +0800
Subject: [PATCH] Create ani2gif.py

---
 ani2gif.py | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 ani2gif.py

diff --git a/ani2gif.py b/ani2gif.py
new file mode 100644
index 0000000..1231505
--- /dev/null
+++ b/ani2gif.py
@@ -0,0 +1,66 @@
+from PIL import Image
+import io,os,sys
+import logging
+
+logging.basicConfig(format='%(asctime)s - %(pathname)s[line:%(lineno)d] - %(levelname)s: %(message)s',level=logging.INFO)
+
+def analyzeANIFile(filePath):
+    with open(filePath,'rb') as f:
+        if f.read(4) != b'RIFF':
+            return {"code":-1,"msg":"File is not a ANI File!"}
+        logging.debug('文件头检查完成！')
+        fileSize = int.from_bytes(f.read(4), byteorder='little', signed=False)
+        # if os.path.getsize(filePath) != fileSize:
+        #     return {"code":-2,"msg":"File is damaged!"}
+        logging.debug('文件长度检查完成！')
+        if f.read(4) != b'ACON':
+            return {"code":-1,"msg":"File is not a ANI File!"}
+        logging.debug('魔数检查完成！')
+        frameRate = (1/60)*1000
+        while(True):
+            chunkName = f.read(4)
+            if chunkName == b'LIST':
+                break
+            chunkSize = int.from_bytes(f.read(4), byteorder='little', signed=False)
+            if chunkName.lower() == b'rate':
+                logging.debug('发现自定义速率！')
+                frameRate = frameRate * int.from_bytes(f.read(4), byteorder='little', signed=False)
+                logging.warning('发现自定义速率！由于GIF限制，将取第一帧与第二帧的速率作为整体速率！')
+                f.read(chunkSize - 4)
+            else:
+                logging.debug('发现自定义Chunk！')
+                f.read(chunkSize)
+        listChunkSize = int.from_bytes(f.read(4), byteorder='little', signed=False)
+        if f.read(4) != b'fram':
+            return {"code":-3,"msg":"File not a ANI File!(No Frames)"}
+        logging.debug('frame头检查完成！')
+        frameList = []
+        nowSize = 4
+        while(nowSize < listChunkSize):
+            if f.read(4) != b'icon':
+                return {"code":-4,"msg":"File not a ANI File!(Other Kind Frames)"}
+            nowSize += 4
+            subChunkSize = int.from_bytes(f.read(4), byteorder='little', signed=False)
+            nowSize += 4
+            frameList.append(f.read(subChunkSize))
+            nowSize += subChunkSize
+        return {"code":0,"msg":frameList,"frameRate":frameRate}
+
+if __name__ == '__main__':
+    if len(sys.argv) < 2:
+        logging.fatal("Usage:python ani2gif.py <inputFile> <outputFile,Option>")
+    else:
+        res = analyzeANIFile(sys.argv[1])
+        GIFframes = []
+        if res["code"] == 0:
+            logging.info('ANI文件分析完成，帧提取完成！')
+            for frame in res["msg"]:
+                frameImage = Image.open(io.BytesIO(frame),formats=['CUR']).convert('RGBA')
+                GIFframes.append(frameImage)
+            if(len(sys.argv) >= 3):
+                GIFframes[0].save(sys.argv[2],format="GIF",save_all=True, append_images=GIFframes[1:], optimize=False, duration=res["frameRate"], loop=0, transparency=0, disposal=2)
+            else:
+                GIFframes[0].save(f"{sys.argv[1].strip('.ani')}.gif",format="GIF",save_all=True, append_images=GIFframes[1:], optimize=False, duration=res["frameRate"], loop=0, transparency=0, disposal=2)
+            logging.info('GIF生成完成！')
+        else:
+            logging.fatal(res["msg"])