byte

问题 I'm creating a system to share video with opencv but I've got a problem. I've a server and a client but when I send informations to the server, the must be bytes. I send 2 things: ret, frame = cap.read() ret is a booland frame is the data video, a numpy.ndarray ret is not a problem but frame: I convert it in string and then in bytes: frame = str(frame).encode() connexion_avec_serveur.send(frame) I'd like now to convert again frame in a numpy.ndarray. 回答1: Your str(frame).encode() is wrong. If

问题 I have a byte[] that I want to convert to an Image and display the image in a label. The byte[] is of a jpeg 2000 format. I have tried the code below but it returns null: InputStream in = new ByteArrayInputStream(bytearray); BufferedImage image = ImageIO.read(in); The image value comes back as null . I want to be able to display the image in a label like below: jLabel.setIcon(new ImageIcon(image)); Thanks 回答1: To convert an array of bytes, i.e. byte[] into an Image , use getImage() . Probably

问题 I have a byte[] that I want to convert to an Image and display the image in a label. The byte[] is of a jpeg 2000 format. I have tried the code below but it returns null: InputStream in = new ByteArrayInputStream(bytearray); BufferedImage image = ImageIO.read(in); The image value comes back as null . I want to be able to display the image in a label like below: jLabel.setIcon(new ImageIcon(image)); Thanks 回答1: To convert an array of bytes, i.e. byte[] into an Image , use getImage() . Probably

问题 This is my code to convert byte data to float. I tried every answers given in this site. I am getting exponential value for this "<44fa0000>" byte data static func returnFloatValue(mutableData:NSMutableData)->Float { let qtyRange = mutableData.subdataWithRange(NSMakeRange(0, 4)) let qtyString = String(qtyRange) let qtyTrimString = qtyString.stringByTrimmingCharactersInSet(NSCharacterSet(charactersInString: "<>")) let qtyValue = Float(strtoul(qtyTrimString, nil, 16)/10) return qtyValue }

问题 I've got a String like this: init_thread = "2b11020000ed" I have to send this string via bluetooth, for what I do this: byte[] init = init_thread.getBytes(); GlobalVar.mTransmission.write(init); What I need is to define that the init_thread string is an hex string before converting it to bytes, because if I do this way, it is getting it wrong: What is doing now = 2(1byte), b(1byte), 1(1byte), 1(1byte)... What must do = 2b(1byte), 11(1byte), 02(1byte)... 回答1: Convert hex to byte and byte to

问题 I am looking for a fastest way to convert a byte array of arbitrary length to a hexadecimal string. This question has been fully answered here at StackOverflow for C#. Some solutions in C++ can be found here. Are there any "turnkey" or "ready-made" solutions to a problem? C-style solutions are welcome. 回答1: #include <vector> #include <iostream> #include <algorithm> #include <string> #include <iterator> #include <sstream> #include <iomanip> int main() { std::vector<unsigned char> v; v.push

问题 Is there an easy and elegant way to convert an unsigned byte value to a signed byte value in java? For example, if all I have is the int value 240 (in binary (24 bits + 11110000) = 32bits), how can I get the signed value for this int? 回答1: Java does not have unsigned values, except for char . Consider this snippet: byte val = (byte)255; System.out.println(String.valueOf(val)); The result will be -1, because the lowest 8 bits got copied over to the byte variable. 回答2: In Java all the primitive

问题 Native method from dll works in java if the input parameter is array of bytes - byte[]. If we use the same method from c# it throws EntryPointNotFoundException. Is that because of byte[] in java and c# are different things? and if it's so how should I use native function from c#? 回答1: Java lacks the unsigned types. In particular, Java lacks a primitive type for an unsigned byte. The Java byte type is signed, while the C# byte is unsigned and sbyte is signed. 回答2: Is that because of byte[] in

问题 I'm writing a program that will parse an Apache log file periodically to log it's visitors, bandwidth usage, etc.. The problem is, I don't want to open the log and parse data I've already parsed. For example: line1 line2 line3 If I parse that file, I'll save all the lines then save that offset. That way, when I parse it again, I get: line1 line2 line3 - The log will open from this point line4 line5 Second time round, I'll get line4 and line5. Hopefully this makes sense... What I need to know

问题 I have a single byte which contains two values. Here's the documentation: The authority byte is split into two fields. The three least significant bits carry the user’s authority level (0-5). The five most significant bits carry an override reject threshold. If these bits are set to zero, the system reject threshold is used to determine whether a score for this user is considered an accept or reject. If they are not zero, then the value of these bits multiplied by ten will be the threshold