1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
//! iTunes Cover Flow format reader.
use super::misc::mktag;
use crate::error::{Error, Result};
use crate::tag::Tag;
use crate::value::Value;
pub fn read_itc(data: &[u8]) -> Result<Vec<Tag>> {
// First block must be 'itch' with size >= 0x1c
if data.len() < 8 {
return Err(Error::InvalidData("not an ITC file".into()));
}
let first_size = u32::from_be_bytes([data[0], data[1], data[2], data[3]]) as usize;
if &data[4..8] != b"itch" || !(0x1c..0x10000).contains(&first_size) {
return Err(Error::InvalidData("not an ITC file".into()));
}
let mut tags = Vec::new();
let mut pos = 0usize;
while pos + 8 <= data.len() {
let block_size =
u32::from_be_bytes([data[pos], data[pos + 1], data[pos + 2], data[pos + 3]]) as usize;
let block_tag = &data[pos + 4..pos + 8];
if !(8..0x80000000).contains(&block_size) {
break;
}
if pos + block_size > data.len() {
break;
}
if block_tag == b"itch" {
// Header block: DataType is at offset 0x10 (16) within block body
let body_start = pos + 8;
let body_end = pos + block_size;
let body = &data[body_start..body_end];
if body.len() >= 20 {
let _data_type = &body[0x10 - 8 + 8..]; // offset 0x10 from block start = 0x08 from body
// Actually offset 0x10 from the block start means byte 16 from pos
// body starts at pos+8, so offset 16 from pos = body[8..12]
let dt_bytes = &data[pos + 16..pos + 20];
let dt_str = match dt_bytes {
b"artw" => "Artwork",
_ => "Unknown",
};
tags.push(mktag(
"ITC",
"DataType",
"Data Type",
Value::String(dt_str.into()),
));
}
} else if block_tag == b"item" {
// Read inner length (4 bytes after block header)
if pos + 12 > data.len() {
break;
}
let inner_len =
u32::from_be_bytes([data[pos + 8], data[pos + 9], data[pos + 10], data[pos + 11]])
as usize;
if inner_len < 0xd0 || inner_len > block_size {
break;
}
// Remaining image data size
let image_size = block_size - inner_len;
// Skip past 4-byte blocks until null terminator
// Starting after block_header(8) + inner_len_field(4) = pos+12
let mut scan = pos + 12;
let mut remaining = inner_len - 12;
loop {
if remaining < 4 || scan + 4 > data.len() {
break;
}
let word = &data[scan..scan + 4];
remaining -= 4;
scan += 4;
if word == b"\0\0\0\0" {
break;
}
}
if remaining < 4 {
break;
}
// Read remaining header
let hdr_start = scan;
let hdr_len = remaining;
if hdr_start + hdr_len > data.len() {
break;
}
let hdr = &data[hdr_start..hdr_start + hdr_len];
// Verify 'data' marker at offset 0xb0
if hdr.len() < 0xb4 || &hdr[0xb0..0xb4] != b"data" {
break;
}
// Parse ITC::Item fields (FORMAT = int32u, FIRST_ENTRY = 0)
// Entry 0 (offset 0*4=0): LibraryID = undef[8] → hex string
if hdr.len() >= 8 {
let lib_id = &hdr[0..8];
let hex: String = lib_id.iter().map(|b| format!("{:02X}", b)).collect();
tags.push(mktag("ITC", "LibraryID", "Library ID", Value::String(hex)));
}
// Entry 2 (offset 2*4=8): TrackID = undef[8] → hex string
if hdr.len() >= 16 {
let track_id = &hdr[8..16];
let hex: String = track_id.iter().map(|b| format!("{:02X}", b)).collect();
tags.push(mktag("ITC", "TrackID", "Track ID", Value::String(hex)));
}
// Entry 4 (offset 4*4=16): DataLocation = undef[4]
if hdr.len() >= 20 {
let loc = &hdr[16..20];
let loc_str = match loc {
b"down" => "Downloaded Separately",
b"locl" => "Local Music File",
_ => "Unknown",
};
tags.push(mktag(
"ITC",
"DataLocation",
"Data Location",
Value::String(loc_str.into()),
));
}
// Entry 5 (offset 5*4=20): ImageType = undef[4]
if hdr.len() >= 24 {
let img_type = &hdr[20..24];
let type_str = match img_type {
b"PNGf" => "PNG",
b"\0\0\0\x0d" => "JPEG",
_ => "Unknown",
};
tags.push(mktag(
"ITC",
"ImageType",
"Image Type",
Value::String(type_str.into()),
));
}
// Entry 7 (offset 7*4=28): ImageWidth = int32u
if hdr.len() >= 32 {
let width = u32::from_be_bytes([hdr[28], hdr[29], hdr[30], hdr[31]]);
tags.push(mktag("ITC", "ImageWidth", "Image Width", Value::U32(width)));
}
// Entry 8 (offset 8*4=32): ImageHeight = int32u
if hdr.len() >= 36 {
let height = u32::from_be_bytes([hdr[32], hdr[33], hdr[34], hdr[35]]);
tags.push(mktag(
"ITC",
"ImageHeight",
"Image Height",
Value::U32(height),
));
}
// ImageData (binary data after item header)
if image_size > 0 {
let img_start = pos + block_size - image_size;
if img_start + image_size <= data.len() {
let img_data = data[img_start..img_start + image_size].to_vec();
tags.push(mktag(
"ITC",
"ImageData",
"Image Data",
Value::Binary(img_data),
));
}
}
}
pos += block_size;
}
Ok(tags)
}