ID3V2.3、ETCO帧事件格式说明 [英] ID3V2.3, ETCO Frame Event Format Clarification

问题描述

根据非正式标准，ETCO 帧是帧头(十字节)，后跟时间戳格式(一字节).然后是一系列事件类型，时间戳"形式的事件(事件类型是一个字节，而时间戳em> 是每个事件 5 个字节).

According to the informal standard, an ETCO frame is the frame header (ten bytes), followed by a time stamp format (one byte). This is then followed by a series of events of the form "Type of Event, Time Stamp" (Type of Event is one byte, while Time Stamp is five bytes per event).

人们如何知道有多少事件?程序是否需要使用帧头的大小字段?

How can someone figure out how many events there are? Would a program need to use the size field of the frame header?

如果所有事件的长度都是 5 个字节，那么 0xFF 事件的目的是什么，其目的是后面还有一个字节的事件"?

If all events are five bytes in length, what's the purpose of the 0xFF event, whose purpose is "One more byte of event follows"?

来源:http://id3.org/id3v2.3.0#sec4.6

推荐答案

1. 是的，您必须解析整个框架才能找到答案.估计 (帧大小)减去(标题大小)除以 5 将为您提供两者的最可能计数，但实际上可能会发生更多事件和更少时间戳.
2. 我自己从未遇到过这种情况，但假设它是为了将具有相同时间戳的多个事件组合在一起.可能会发生字节 $FF$FF$05$06$0D 而不是只有一个事件(即 $0D 表示不需要的噪声)，这表明后面还有两个字节=事件(即结尾结束、诗歌开始、不需要的噪音——所有这些都在同一个时间戳，然后是 4 个字节).

1. Yes, you must parse the entire frame to find out. Estimating (size of frame) minus (header size), divided by 5 would give you the most probable count of both, but in reality more events and fewer timestamps might occur.
2. I've never encountered that situation myself, but assume it's for combining multiple events with the same timestamp. Instead of only having one event (i.e. $0D for unwanted noise) the bytes $FF$FF$05$06$0D might occur, indicating that two more bytes=events are following (i.e. outro ends, verse starts, unwanted noise - all at the same timestamp, whose 4 bytes then follow).

这篇关于ID3V2.3、ETCO帧事件格式说明的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！