如何用Automator或AppleScript按WEBM分割.dat文件为.webm文件

方案一：独立AppleScript脚本 #

直接用AppleScript调用shell工具处理二进制文件分割，操作步骤如下：

1. 打开「脚本编辑器」（Launchpad → 其他文件夹）
2. 复制以下代码到编辑器中：

set inputFile to choose file with prompt "选择要分割的.dat文件"
set inputPath to POSIX path of inputFile
set outputFolder to choose folder with prompt "选择保存.webm文件的文件夹"
set outputPath to POSIX path of outputFolder

-- 获取所有"WEBM"字符串的字节偏移位置
set offsetList to do shell script "grep -aob 'WEBM' " & quoted form of inputPath & " | cut -d: -f1"
set offsets to paragraphs of offsetList

if offsets is {} then
    display alert "错误" message "文件中未找到WEBM标记"
    return
end if

-- 分割每个片段：从上次分割点到当前WEBM之前的内容
set prevOffset to 0
repeat with i from 1 to count of offsets
    set currentOffset to item i of offsets as integer
    set outputFileName to outputPath & "segment_" & (text -2 thru -1 of ("0" & i)) & ".webm"
    do shell script "dd if=" & quoted form of inputPath & " of=" & quoted form of outputFileName & " bs=1 skip=" & prevOffset & " count=" & (currentOffset - prevOffset)
    set prevOffset to currentOffset
end repeat

-- 处理最后一段：从最后一个WEBM到文件末尾
set fileSize to do shell script "stat -f %z " & quoted form of inputPath as integer
set lastOutputFileName to outputPath & "segment_" & (text -2 thru -1 of ("0" & (count of offsets + 1))) & ".webm"
do shell script "dd if=" & quoted form of inputPath & " of=" & quoted form of lastOutputFileName & " bs=1 skip=" & prevOffset & " count=" & (fileSize - prevOffset)

display alert "完成" message "已分割出" & (count of offsets + 1) & "个.webm文件"

3. 点击编辑器顶部的「运行」按钮，按提示选择目标.dat文件和输出文件夹即可。

方案二：Automator快速操作（右键直接处理） #

如果需要右键快速处理文件，可创建Automator快速操作：

1. 打开「Automator」，新建「快速操作」
2. 顶部设置：「工作流收到当前」选择「文件或文件夹」，「在」选择「访达」
3. 添加「运行AppleScript」动作，替换为以下代码：

on run {input, parameters}
    set inputFile to item 1 of input
    set inputPath to POSIX path of inputFile
    set outputFolder to choose folder with prompt "选择保存.webm文件的文件夹"
    set outputPath to POSIX path of outputFolder

    set offsetList to do shell script "grep -aob 'WEBM' " & quoted form of inputPath & " | cut -d: -f1"
    set offsets to paragraphs of offsetList

    if offsets is {} then
        display alert "错误" message "文件中未找到WEBM标记"
        return input
    end if

    set prevOffset to 0
    repeat with i from 1 to count of offsets
        set currentOffset to item i of offsets as integer
        set outputFileName to outputPath & "segment_" & (text -2 thru -1 of ("0" & i)) & ".webm"
        do shell script "dd if=" & quoted form of inputPath & " of=" & quoted form of outputFileName & " bs=1 skip=" & prevOffset & " count=" & (currentOffset - prevOffset)
        set prevOffset to currentOffset
    end repeat

    set fileSize to do shell script "stat -f %z " & quoted form of inputPath as integer
    set lastOutputFileName to outputPath & "segment_" & (text -2 thru -1 of ("0" & (count of offsets + 1))) & ".webm"
    do shell script "dd if=" & quoted form of inputPath & " of=" & quoted form of lastOutputFileName & " bs=1 skip=" & prevOffset & " count=" & (fileSize - prevOffset)

    display alert "完成" message "已分割出" & (count of offsets + 1) & "个.webm文件"
    return input
end run

4. 保存快速操作（比如命名为「拆分dat为webm」），之后在访达中右键点击.dat文件，即可在「快速操作」菜单中找到该功能。

注意事项 #

• 如果.dat文件体积很大，dd命令可能会较慢（因为bs=1是按字节读取），可以尝试将bs改为更大的值（比如bs=4096），但需确保count计算准确；
• 代码中grep -aob的-a参数用于强制将二进制文件视为文本文件处理，确保能找到"WEBM"标记。

内容的提问来源于stack exchange，提问作者Maximilian Becker