<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hi Huki,<div class=""><br class=""></div><div class="">Can you supply a bmp file that is broken? Jörg Jenderek made the latest changes and I want to make sure that we understand what's going on before making more changes.</div><div class=""><br class=""></div><div class="">Best,</div><div class=""><br class=""></div><div class="">christos<br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Feb 27, 2020, at 10:08 PM, Huki <<a href="mailto:gk7huki@gmail.com" class="">gk7huki@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" class="">
<div defanged_smarttemplateinserted="true" class=""><p class=""><defanged_div id="smartTemplate4-template" class="">Hi,<br class="">
<br class="">
Any news regarding the fix for broken bitmaps? I noticed my email
was filtered because of too big attachments. If it helps, I'm
reposting my patch in plain text.<br class="">
<br class="">
<br class="">
</defanged_div></p><pre class="">diff --git a/magic/Magdir/images b/magic/Magdir/images
index 931df682..3cde072c 100644
--- a/magic/Magdir/images
+++ b/magic/Magdir/images
@@ -613,7 +613,7 @@
0 leshort 40
# skip bad samples like GAME by looking for valid number of color planes
>12 uleshort 1 Device independent bitmap graphic
-!:mime image/bmp
+!:mime image/x-ms-bmp
!:apple ????BMPp
!:ext dib
>>4 lelong x \b, %d x
@@ -639,7 +639,7 @@
>>18 leshort x \b, %d x
>>20 leshort x %d
>14 leshort 64 PC bitmap, OS/2 2.x format
-!:mime image/bmp
+!:mime image/x-ms-bmp
!:apple ????BMPp
!:ext bmp
# image width and height fields are unsigned integers for OS/2
@@ -660,7 +660,7 @@
#>>(10.l) ubequad !0 \b, bits 0x%16.16llx
# BITMAPV2INFOHEADER adds RGB bit masks
>14 leshort 52 PC bitmap, Adobe Photoshop
-!:mime image/bmp
+!:mime image/x-ms-bmp
!:apple ????BMPp
!:ext bmp
>>18 lelong x \b, %d x
@@ -668,54 +668,52 @@
>>28 leshort x %d
# BITMAPV3INFOHEADER adds alpha channel bit mask
>14 leshort 56 PC bitmap, Adobe Photoshop with alpha channel mask
-!:mime image/bmp
+!:mime image/x-ms-bmp
!:apple ????BMPp
!:ext bmp
>>18 lelong x \b, %d x
>>22 lelong x %d x
>>28 leshort x %d
->14 leshort 40
-# jump 4 bytes before end of file/header to skip fmt-116-signature-id-118.dib
->>(2.l-4) ulong x PC bitmap, Windows 3.x format
-!:mime image/bmp
+>14 leshort 40 PC bitmap, Windows 3.x format
+!:mime image/x-ms-bmp
!:apple ????BMPp
->>>18 lelong x \b, %d x
->>>22 lelong x %d
+>>18 lelong x \b, %d x
+>>22 lelong x %d
# 320 x 400 <a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/LOGO.SYS">https://en.wikipedia.org/wiki/LOGO.SYS</a>
->>>18 ulequad =0x0000019000000140 x
+>>18 ulequad =0x0000019000000140 x
!:ext bmp/sys
->>>18 ulequad !0x0000019000000140
+>>18 ulequad !0x0000019000000140
# compression method 2~RLE 4-bit/pixel implies also extension rle
->>>>30 ulelong 2 x
+>>>30 ulelong 2 x
!:ext bmp/rle
->>>>30 default x x
+>>>30 default x x
!:ext bmp
# number of bits per pixel (color depth); found 1 2 4 8 16 24 32
->>>28 leshort x %d
+>>28 leshort x %d
# x, y coordinates of the hotspot; there is no hotspot in bitmaps, so values 0
-#>>>6 uleshort >0 \b, hotspot %ux
-#>>>>8 uleshort x \b%u
+#>>6 uleshort >0 \b, hotspot %ux
+#>>>8 uleshort x \b%u
# number of color planes (must be 1), except badplanes.bmp for testing
-#>>>26 uleshort >1 \b, %u color planes
+#>>26 uleshort >1 \b, %u color planes
# compression method: 0~no 1~RLE 8-bit/pixel 2~RLE 4-bit/pixel 3~Huffman 1D 6~RGBA bit field masks
-#>>>30 ulelong 3 \b, Huffman 1D compression
->>>30 ulelong >0 \b, %u compression
+#>>30 ulelong 3 \b, Huffman 1D compression
+>>30 ulelong >0 \b, %u compression
# image size is the size of raw bitmap; a dummy 0 can be given for BI_RGB bitmaps
->>>34 ulelong >0 \b, image size %u
+>>34 ulelong >0 \b, image size %u
# horizontal and vertical resolution of the image (pixel per metre, signed integer)
->>>38 lelong >0 \b, resolution %d x
->>>>42 lelong x %d px/m
+>>38 lelong >0 \b, resolution %d x
+>>>42 lelong x %d px/m
# number of colors in palette 16 256, or 0 to default to 2**n
-#>>>46 ulelong >0 \b, %u colors
+#>>46 ulelong >0 \b, %u colors
# number of important colors used, or 0 when every color is important
->>>50 ulelong >0 \b, %u important colors
+>>50 ulelong >0 \b, %u important colors
# cbSize; often size of file
->>>2 ulelong x \b, cbSize %u
-#>>>2 ulelong x \b, cbSize 0x%x
+>>2 ulelong x \b, cbSize %u
+#>>2 ulelong x \b, cbSize 0x%x
# offBits; offset to bitmap data like 36h 76h BEh 236h 406h 436h 4E6h
->>>10 ulelong x \b, bits offset %u
-#>>>10 ulelong x \b, bits offset 0x%x
-#>>>(10.l) ubequad !0 \b, bits 0x%16.16llxd
+>>10 ulelong x \b, bits offset %u
+#>>10 ulelong x \b, bits offset 0x%x
+#>>(10.l) ubequad !0 \b, bits 0x%16.16llxd
>14 leshort 124 PC bitmap, Windows 98/2000 and newer format
!:mime image/x-ms-bmp
>>18 lelong x \b, %d x
</pre>
<br class="">
<hr defanged_style="width:100%; height:1px; border:0; color:#B5C4DF;
background-color:#B5C4DF" class="">
<defanged_span class="">
<b class="">From:</b> Huki <a class="moz-txt-link-rfc2396E" href="mailto:gk7huki@gmail.com"><gk7huki@gmail.com></a><br class="">
<b class="">Sent:</b> Sun, 2 Feb 2020 04:22:49 +0530<br class="">
<b class="">To:</b> file <a class="moz-txt-link-rfc2396E" href="mailto:file@astron.com"><file@astron.com></a><br class="">
<b class="">Subject:</b> [File] [PATCH] Fix broken BMP detection since
5.38
</defanged_span>
<br class="">
<br class=""><div class=""><br class="webkit-block-placeholder"></div><defanged_div class=""><p class=""><defanged_div class="replaced-blockquote" cite="mid:c626f4a6-bf8e-d994-aa9a-83b19e608a81@gmail.com" type="cite">
</defanged_div></p><pre class="moz-quote-pre" wrap="">Since updating to File 5.38, bitmap images with header size 40 (Windows
3.x format) aren't detected under certain conditions. It seems to happen
when the file size is > 1MB (eg, a 1024 x 1024 RGB image).
$ file test.bmp
test.bmp: data
I traced down the issue to this recently added line:
# jump 4 bytes before end of file/header to skip
fmt-116-signature-id-118.dib
>>(2.l-4) ulong x PC bitmap, Windows 3.x format
It's a bit weird and I don't see any reason to do this. I removed this
(and adjusted the lines below) and the detection is working again.
$ file -m magic.mgc test.bmp
test.bmp: PC bitmap, Windows 3.x format, 1024 x 1024 x 24, image size
3145728, resolution 11811 x 11811 px/m, cbSize 3145782, bits offset 54
Also, I changed the mimetype to consistently use image/x-ms-bmp as
opposed to image/bmp in some places.
I've attached the patch and the test bitmap file.
Regards,
Huki
</pre><div class=""><br class="webkit-block-placeholder"></div><defanged_div class="">
<br class="">
</defanged_div></defanged_div></div>
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