获取图像的实际位深度
Getting the actual bit depth of an image
即使图像保存为 16 位文件，它通常也来自仅产生 10 或 12 位的相机。我希望能够检查图像文件的某些位和哪些位是否始终为零。
即相机产生 XXXXXXXXXXXX，它被写为 XXXXXXXXXXXX0000 或 0000XXXXXXXXXXXX
编辑：这里以4个文件为例，8bit，10bit，12bit，16bit：https://filesender.uninett.no/?s=download&token=6a6f7f90-708d-4636-ba71-949acaaaded3
您可以在 shell 中使用 ImageMagick 获得位深度：
magick identify -format "%[bit-depth]" 12-bit_000000.dpx
12
或者，一次性获取所有文件，在文件名前加前缀：
magick identify -format "%f: %[bit-depth]\n" *.dpx
10-bit_000000.dpx: 10
12-bit_000000.dpx: 12
16-bit_000000.dpx: 16
8-bit_000000.dpx: 8
您可以像这样查看所有其他详细信息：
magick identify -verbose 12-bit_000000.dpx
示例输出
Image:
Filename: 12-bit_000000.dpx
Format: DPX (SMPTE 268M-2003 (DPX 2.0))
Class: DirectClass
Geometry: 2048x1536+0+0
Units: Undefined
Colorspace: sRGB
Type: TrueColor
Endianness: LSB
Depth: 12-bit
Channel depth:
Red: 12-bit
Green: 12-bit
Blue: 12-bit
Channel statistics:
Pixels: 3145728
Red:
min: 0 (0)
max: 2373 (0.579487)
mean: 502.223 (0.122643)
...
...
您可以获得 大量 十六进制像素转储，如下所示：
magick 12-bit_000000.dpx txt:
示例输出
...
...
118,2: (6897.58,6977.6,8017.83) #1AF21B421F52 srgb(10.525%,10.6471%,12.2344%)
119,2: (6945.59,7121.63,8033.84) #1B221BD21F62 srgb(10.5983%,10.8669%,12.2589%)
120,2: (6769.55,7329.68,7921.81) #1A721CA21EF2 srgb(10.3297%,11.1844%,12.0879%)
121,2: (6465.48,7441.7,7825.79) #19411D121E92 srgb(9.86569%,11.3553%,11.9414%)
...
...
你可以这样找到最亮的像素：
identify -define identify:locate=maximum 12-bit_000000.dpx
Channel maximum locations:
Red: 37976.7 (0.579487) 1144,1311
Green: 36376.3 (0.555067) 1146,1311
Blue: 34808 (0.531136) 1146,1314
这告诉你最亮的区域在 (1144,1311) 附近，因此我们可以裁剪出该 4x4 区域并将其转储为十六进制：
magick 12-bit_000000.dpx -crop 4x4+1144+1311 txt:
# ImageMagick pixel enumeration: 4,4,65535,srgb
0,0: (37976.7,36040.2,34407.9) #94598CC88668 srgb(57.9487%,54.9939%,52.5031%)
1,0: (37672.6,36248.3,34455.9) #93298D988698 srgb(57.4847%,55.3114%,52.5763%)
2,0: (37208.5,36376.3,34407.9) #91598E188668 srgb(56.7766%,55.5067%,52.5031%)
3,0: (36808.4,36088.3,34055.8) #8FC88CF88508 srgb(56.1661%,55.0672%,51.9658%)
0,1: (37880.7,35704.2,34055.8) #93F98B788508 srgb(57.8022%,54.4811%,51.9658%)
1,1: (37544.6,36040.2,34151.8) #92A98CC88568 srgb(57.2894%,54.9939%,52.1123%)
2,1: (37416.6,36360.3,34407.9) #92298E088668 srgb(57.094%,55.4823%,52.5031%)
3,1: (37096.5,35992.2,34055.8) #90E88C988508 srgb(56.6056%,54.9206%,51.9658%)
0,2: (37768.6,35592.1,33991.8) #93898B0884C8 srgb(57.6313%,54.3101%,51.8681%)
1,2: (37544.6,35960.2,34183.8) #92A98C788588 srgb(57.2894%,54.8718%,52.1612%)
2,2: (37528.6,35992.2,34487.9) #92998C9886B8 srgb(57.265%,54.9206%,52.6252%)
3,2: (37464.6,35560.1,34279.8) #92598AE885E8 srgb(57.1673%,54.2613%,52.3077%)
0,3: (37560.6,35624.2,34263.8) #92B98B2885D8 srgb(57.3138%,54.359%,52.2833%)
1,3: (37336.5,35816.2,34519.9) #91D98BE886D8 srgb(56.9719%,54.652%,52.674%)
2,3: (37544.6,35640.2,34808) #92A98B3887F8 srgb(57.2894%,54.3834%,53.1136%)
3,3: (37688.6,34968,34439.9) #933988988688 srgb(57.5092%,53.3578%,52.5519%)
希望你能看到每个样本的十六进制以 8 结尾，这意味着底部 3 位是清晰的。
有 Python 绑定到 ImageMagick，称为 wand。
另一个选项完全是 exiftool:
exiftool 10-bit_000000.dpx
示例输出
ExifTool Version Number : 12.00
File Name : 10-bit_000000.dpx
Directory : .
File Size : 12 MB
File Modification Date/Time : 2021:02:08 09:50:32+00:00
File Access Date/Time : 2021:02:08 09:59:45+00:00
File Inode Change Date/Time : 2021:02:08 09:50:32+00:00
File Permissions : rw-r--r--
File Type : DPX
File Type Extension : dpx
MIME Type : image/x-dpx
Byte Order : Little-endian
Header Version : V2.0
DPX File Size : 12584960
Ditto Key : New
Image File Name : 10-bit_000000.dpx
Create Date : 2021:02:01 10:45:32
Creator : flashSuite 2 3.4.5
Project : Colour test
Copyright : 2021
Encryption Key : ffffffff
Orientation : Horizontal (normal)
Image Elements : 1
Image Width : 2048
Image Height : 1536
Data Sign : Unsigned
Components Configuration : R, G, B
Bit Depth : 10 <--- HERE IT IS
Image Description :
Source File Name :
Source Create Date :
Input Device Name : SpinnerS
Input Device Serial Number : 5CFC3FE89CDB
Frame Rate : 16
Frame ID :
Slate Information :
User ID :
Image Size : 2048x1536
Megapixels : 3.1
即使图像保存为 16 位文件，它通常也来自仅产生 10 或 12 位的相机。我希望能够检查图像文件的某些位和哪些位是否始终为零。
即相机产生 XXXXXXXXXXXX，它被写为 XXXXXXXXXXXX0000 或 0000XXXXXXXXXXXX
编辑：这里以4个文件为例，8bit，10bit，12bit，16bit：https://filesender.uninett.no/?s=download&token=6a6f7f90-708d-4636-ba71-949acaaaded3
您可以在 shell 中使用 ImageMagick 获得位深度：
magick identify -format "%[bit-depth]" 12-bit_000000.dpx
12
或者，一次性获取所有文件，在文件名前加前缀：
magick identify -format "%f: %[bit-depth]\n" *.dpx
10-bit_000000.dpx: 10
12-bit_000000.dpx: 12
16-bit_000000.dpx: 16
8-bit_000000.dpx: 8
您可以像这样查看所有其他详细信息：
magick identify -verbose 12-bit_000000.dpx
示例输出
Image:
Filename: 12-bit_000000.dpx
Format: DPX (SMPTE 268M-2003 (DPX 2.0))
Class: DirectClass
Geometry: 2048x1536+0+0
Units: Undefined
Colorspace: sRGB
Type: TrueColor
Endianness: LSB
Depth: 12-bit
Channel depth:
Red: 12-bit
Green: 12-bit
Blue: 12-bit
Channel statistics:
Pixels: 3145728
Red:
min: 0 (0)
max: 2373 (0.579487)
mean: 502.223 (0.122643)
...
...
您可以获得 大量 十六进制像素转储，如下所示：
magick 12-bit_000000.dpx txt:
示例输出
...
...
118,2: (6897.58,6977.6,8017.83) #1AF21B421F52 srgb(10.525%,10.6471%,12.2344%)
119,2: (6945.59,7121.63,8033.84) #1B221BD21F62 srgb(10.5983%,10.8669%,12.2589%)
120,2: (6769.55,7329.68,7921.81) #1A721CA21EF2 srgb(10.3297%,11.1844%,12.0879%)
121,2: (6465.48,7441.7,7825.79) #19411D121E92 srgb(9.86569%,11.3553%,11.9414%)
...
...
你可以这样找到最亮的像素：
identify -define identify:locate=maximum 12-bit_000000.dpx
Channel maximum locations:
Red: 37976.7 (0.579487) 1144,1311
Green: 36376.3 (0.555067) 1146,1311
Blue: 34808 (0.531136) 1146,1314
这告诉你最亮的区域在 (1144,1311) 附近，因此我们可以裁剪出该 4x4 区域并将其转储为十六进制：
magick 12-bit_000000.dpx -crop 4x4+1144+1311 txt:
# ImageMagick pixel enumeration: 4,4,65535,srgb
0,0: (37976.7,36040.2,34407.9) #94598CC88668 srgb(57.9487%,54.9939%,52.5031%)
1,0: (37672.6,36248.3,34455.9) #93298D988698 srgb(57.4847%,55.3114%,52.5763%)
2,0: (37208.5,36376.3,34407.9) #91598E188668 srgb(56.7766%,55.5067%,52.5031%)
3,0: (36808.4,36088.3,34055.8) #8FC88CF88508 srgb(56.1661%,55.0672%,51.9658%)
0,1: (37880.7,35704.2,34055.8) #93F98B788508 srgb(57.8022%,54.4811%,51.9658%)
1,1: (37544.6,36040.2,34151.8) #92A98CC88568 srgb(57.2894%,54.9939%,52.1123%)
2,1: (37416.6,36360.3,34407.9) #92298E088668 srgb(57.094%,55.4823%,52.5031%)
3,1: (37096.5,35992.2,34055.8) #90E88C988508 srgb(56.6056%,54.9206%,51.9658%)
0,2: (37768.6,35592.1,33991.8) #93898B0884C8 srgb(57.6313%,54.3101%,51.8681%)
1,2: (37544.6,35960.2,34183.8) #92A98C788588 srgb(57.2894%,54.8718%,52.1612%)
2,2: (37528.6,35992.2,34487.9) #92998C9886B8 srgb(57.265%,54.9206%,52.6252%)
3,2: (37464.6,35560.1,34279.8) #92598AE885E8 srgb(57.1673%,54.2613%,52.3077%)
0,3: (37560.6,35624.2,34263.8) #92B98B2885D8 srgb(57.3138%,54.359%,52.2833%)
1,3: (37336.5,35816.2,34519.9) #91D98BE886D8 srgb(56.9719%,54.652%,52.674%)
2,3: (37544.6,35640.2,34808) #92A98B3887F8 srgb(57.2894%,54.3834%,53.1136%)
3,3: (37688.6,34968,34439.9) #933988988688 srgb(57.5092%,53.3578%,52.5519%)
希望你能看到每个样本的十六进制以 8 结尾，这意味着底部 3 位是清晰的。
有 Python 绑定到 ImageMagick，称为 wand。
另一个选项完全是 exiftool:
exiftool 10-bit_000000.dpx
示例输出
ExifTool Version Number : 12.00
File Name : 10-bit_000000.dpx
Directory : .
File Size : 12 MB
File Modification Date/Time : 2021:02:08 09:50:32+00:00
File Access Date/Time : 2021:02:08 09:59:45+00:00
File Inode Change Date/Time : 2021:02:08 09:50:32+00:00
File Permissions : rw-r--r--
File Type : DPX
File Type Extension : dpx
MIME Type : image/x-dpx
Byte Order : Little-endian
Header Version : V2.0
DPX File Size : 12584960
Ditto Key : New
Image File Name : 10-bit_000000.dpx
Create Date : 2021:02:01 10:45:32
Creator : flashSuite 2 3.4.5
Project : Colour test
Copyright : 2021
Encryption Key : ffffffff
Orientation : Horizontal (normal)
Image Elements : 1
Image Width : 2048
Image Height : 1536
Data Sign : Unsigned
Components Configuration : R, G, B
Bit Depth : 10 <--- HERE IT IS
Image Description :
Source File Name :
Source Create Date :
Input Device Name : SpinnerS
Input Device Serial Number : 5CFC3FE89CDB
Frame Rate : 16
Frame ID :
Slate Information :
User ID :
Image Size : 2048x1536
Megapixels : 3.1