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python Image PIL to binary Hex

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问题 from PIL import Image from PIL import ImageDraw from PIL import ImageFont import urllib.request import io import binascii data = urllib.request.urlopen('http://pastebin.ca/raw/2311595').read() r_data = binascii.unhexlify(data) stream = io.BytesIO(r_data) img = Image.open(stream) draw = ImageDraw.Draw(img) font = ImageFont.truetype("arial.ttf",14) draw.text((0, 220),"This is a test11",(0,255,0),font=font) draw = ImageDraw.Draw(img) with open(img,'rb') as in_file: #error on here invalid file:

Writing Byte Array To Binary File Javascript

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问题 I am trying to write a script that generates random numbers these number then are converted to groups of 4Bytes each then these 4-bytes-groups are put into an Uint8Array finally I try to save the array to binary file. Here is my code: <html> <head> <title>Raandom Number Generator</title> </head> <body> <script src="http://code.jquery.com/jquery-1.11.0.min.js"></script> <script src="filesaver.min.js"></script> <script type="text/javascript"> $(function() { if (!Date.now) { Date.now = function(

Can GIT, Mercurial, SVN, or other version control tools work well when project tree has binary files?

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问题 Sometimes our project tree can have binary files, such as jpg, png, doc, xls, or pdf. Can GIT, Mercurial, SVN, or other tools do a good job when only part of a binary file is changed? For example, if the spec is written in .doc and it is part of the repository, then if it is 4MB, and edited 100 times but just for 1 or 2 lines, and checked in 100 times during the year, then it is 400MB. If it is 100 different .doc and .xls files, then it is 40GB... not a size that is easy to manage. I have

Code for searching for a string in a binary file

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I have asked this question a few days ago: How to look for an ANSI string in a binary file? and I got a really nice answer , what later turned into a much harder question: Can input iterators be used where forward iterators are expected? what is now really not on a level what I could understand. I am still learning C++ and I am looking for an easy way to search for a string in a binary file. Could someone show me a simple code for a minimalistic C++ console program which looks for a string in a binary file and outputs the locations to stdout? Possibly, can you show me a version where the file

Efficiently reading few lines from a very large binary file

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Here is a simple example to illustrate my problem: I have a large binary file with 10 million values. I want to get 5K values from certain points in this file. I have a list of indexes giving me the exact place in the file I have my value in. To solve this I tried two methods: Going through the values and simply using seek() (from the start of the file) to get each value, something like this: binaryFile_new = open(binary_folder_path, "r+b") for index in index_list: binaryFile_new.seek (size * (index), 0) wanted_line = binaryFile_new.read (size) wanted_line_list.append(wanted_line) binaryFile

What to put in a binary data file's header

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问题 I have a simulation that reads large binary data files that we create (10s to 100s of GB). We use binary for speed reasons. These files are system dependent, converted from text files on each system that we run, so I'm not concerned about portability. The files currently are many instances of a POD struct, written with fwrite. I need to change the struct, so I want to add a header that has a file version number in it, which will be incremented anytime the struct changes. Since I'm doing this,

Portable C binary serialization primitives

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As far as I know, the C library provides no help in serializing numeric values into a non-text byte stream. Correct me if I'm wrong. The most standard tool in use is htonl et al from POSIX. These functions have shortcomings: There is no 64-bit support. There is no floating-point support. There are no versions for signed types. When deserializing, the unsigned-to-signed conversion relies on signed integral overflow which is UB. Their names do not state the size of the datatype. They depend on 8-bit bytes and the presence of exact-size uint_ N _t. The input types are the same as the output types

Writing files in bit form to a file in C

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I am implementing the huffman algorithm in C. I have got the basic functionality down up to the point where the binary codewords are obtained. so for example, abcd will be 100011000 or something similar. now the question is how do you write this code in binary form in the compressed file. I mean if I write it normally each 1 and 0 will be one character so there is no compression. I need to write those 1s and 0s in their bit form. is that possible in C. if so how? Collect bits until you have enough bits to fill a byte and then write it.. E.g. something like this: int current_bit = 0; unsigned

How to use fread and fwrite functions to read and write Binary files?

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问题 Hi in my project I've to read a .bin file which has sensor data in the form of short(16 bit values) . I'm doing this using fread function into a buffer, but I feel that the reading-in is not happening correctly. I mean there is no consistence between what I write and what I read in. Can you guys suggest what is going wrong here? This is not my code from my project... I'm only trying to verify the fread and fwrite functions here. #include<stdio.h> void main() { FILE *fp = NULL; short x[10] =

Backslash zero delimiter '\0'

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问题 I have seen '\0' to be used as a delimiter in mixed binary files (UTF8 strings + binary data). Could anyone explain what '\0' means or point to a good place to study? 回答1: It's the null character; more info in this Wikipedia article. 回答2: The two-character \0 representation is used in C source code to represent the NUL character, which is the (single) character with ASCII value 0. The NUL character is used in C style character strings to indicate where the end of the string is. For example,