所有CS50使用者，
当前，我正在对pset4进行过滤，反射并在我编写的代码中苦苦挣扎。它可以很好地编译，但是输出图片看起来像我所附的图片。有什么线索可以解决这个问题吗？ （如果可能的话，没有解决方案，那么提示完全没问题：））
#include "helpers.h"
#include <stdio.h>
#include <math.h>
// Convert image to grayscale
void grayscale(int height, int width, RGBTRIPLE image[height][width])
{
for (int i = 0; i < (height - 1); i++)
{
for (int j = 0; j < (width - 1); j++)
{
//get the average
float average = 0;
average = (image[i][j].rgbtRed + image[i][j].rgbtGreen + image[i][j].rgbtBlue) / 3;
//set color channels with the average value
image[i][j].rgbtRed = round(average);
image[i][j].rgbtGreen = round(average);
image[i][j].rgbtBlue = round(average);
}
}
return;
}
// Convert image to sepia
void sepia(int height, int width, RGBTRIPLE image[height][width])
{
for (int i = 0; i < (height - 1); i++)
{
for (int j = 0; j < (width - 1); j++)
{
//calculate the new values
float red = 0;
float green = 0;
float blue = 0;
red = .393 * image[i][j].rgbtRed + .769 * image[i][j].rgbtGreen + .189 * image[i][j].rgbtBlue;
if (round(red) > 255)
{
image[i][j].rgbtRed = 255;
}
else if (round(red <= 255))
{
image[i][j].rgbtRed = red;
}
green = .349 * image[i][j].rgbtRed + .686 * image[i][j].rgbtGreen + .168 * image[i][j].rgbtBlue;
if (round(green) > 255)
{
image[i][j].rgbtGreen = 255;
}
else if (round(green) <= 255)
{
image[i][j].rgbtGreen = green;
}
blue = .272 * image[i][j].rgbtRed + .534 * image[i][j].rgbtGreen + .131 * image[i][j].rgbtBlue;
if (round(blue) > 255)
{
image[i][j].rgbtBlue = 255;
}
else if (round(blue) <= 255)
{
image[i][j].rgbtBlue = blue;
}
}
}
return;
}
// Reflect image horizontally
void reflect(int height, int width, RGBTRIPLE image[height][width])
{
for (int i = 0; i < (height - 1); i++)
{
//RGBTRIPLE
int a[width - 1 /2];
int b[width - 1 /2];
int c[width - 1 /2];
for (int j = 0; j < ((width/2) - 1); j++)
{
a[j] = image[i][(width - 1) - j].rgbtRed;
b[j] = image[i][(width - 1) - j].rgbtGreen;
c[j] = image[i][(width - 1) - j].rgbtBlue;
}
// GERADE / UNGERADE ZAHLEN VERARBEITEN
for (int n = 0; (n + (width - 1) /2) < (width - 1); n++)
{
image[i][((width - 1)/2) - n].rgbtRed = image[i][((width - 1)/2) - n].rgbtRed;
image[i][((width - 1)/2) - n].rgbtGreen = image[i][((width - 1)/2) - n].rgbtGreen;
image[i][((width - 1)/2) - n].rgbtBlue = image[i][((width - 1)/2) - n].rgbtBlue;
}
for (int m = 0; m < ((width/2) - 1); m++)
{
image[i][m].rgbtRed = a[m];
image[i][m].rgbtRed = b[m];
image[i][m].rgbtRed = c[m];
}
}
return;
}
// Blur image
void blur(int height, int width, RGBTRIPLE image[height][width])
{
return;
}
输入：
./filter -r stadium.bmp outfile.bmp
（stadium.bmp只是我选择的文件。您可以选择任何文件作为输入）
输出：编译成功，请参见所附图片enter image description here
答案 0 :(得分：0)
您的代码太复杂。您无需将图像划分为RGB值。您需要从左向右交换图像值，反之亦然，以实现反射。
为此，您可能需要创建一个与“图像”相同的临时数据结构。
temp使用image，您需要存储//Pseudo code
1. //Loop though the row of an image (start from row = 0). We need to iterate every row.
2. // Loop through the height of an image to save current row in an image to the temp.
3. // Swap the values in image by using the temp.
中的值，并交换它们。以下是您可以使用的设计模式。
val1, val2, valn, val3, val4
如果要在下面过滤此一维图像。
val4, val3, valn, val2, val1
经过反射滤镜后，将是这样。
import 'package:flutter/material.dart';
import 'dart:math';
import 'dart:convert';
import 'package:http/http.dart' as http;
import 'dart:async';
import 'package:flutter_app/menu_member.dart';
import 'package:flutter_app/globals.dart' as globals;
class Lotto extends StatefulWidget {
@override
_LottoState createState() => new _LottoState();
}
class _LottoState extends State<Lotto> {
@override
void initState() {
super.initState();
}
var i=1;
var nb_num=49;
var no_select=[];
var no_a_select=5;
List<Color> colorList = List<Color>.generate(49, (int index) => Colors.lightBlue);
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: new AppBar(
title: new Text('GRILLE DE LOTTO'),
),
body:
Center(
child: Column(
children: <Widget>[
Container(
width:400,
height:30,
margin: const EdgeInsets.only(top: 10.0),
child : new Text("Selectionnez 5 numéros",textAlign: TextAlign.center,style: TextStyle(fontSize: 30.0),),
),
Container(
width:400,
height:300,
child: new GridView.count(
crossAxisCount: 9,
padding: const EdgeInsets.all(30.0),
mainAxisSpacing: 4.0,
crossAxisSpacing: 4.0,
children: new List<Widget>.generate(49, (index) {
return new GestureDetector(
onTap: () {
setState(() {
if (colorList[index] == Colors.lightBlue) {
if (no_select.length<no_a_select) {
colorList[index] = Colors.redAccent;
no_select.add(index+1);
}
else {
showDialog(
context: context,
builder: (BuildContext context){
return AlertDialog(
title: Text("INFORMATION"),
content: Text("Vous ne pouvez pas sélectionner plus de 5 numéros !!!"),
);
}
);
}
print(no_select);
}
else {
colorList[index] = Colors.lightBlue;
no_select.remove(index+1);
print(no_select);
}
});
},
child: Container(
child: ClipOval(
child: Container(
color: colorList[index],
height: 20.0,
width: 20.0,
child: Center(
child: new Text((index+1).toString(),
style: TextStyle(color: Colors.white, fontSize: 24),
textAlign: TextAlign.center),
),
),
),
),
);
}
),
),
),
Container(
width:400,
height:30,
margin: const EdgeInsets.only(top: 10),
child : new Text("Vos Numéros",textAlign: TextAlign.center,style: TextStyle(fontSize: 30.0),),
),
Container(
width:400,
height:80,
margin: const EdgeInsets.only(top: 10.0),
decoration: BoxDecoration(
border: Border.all(
color: Colors.lightBlueAccent,
width: 2,
),
borderRadius: BorderRadius.circular(12),
),
child:
getWidget()
),
Container(
width:300,
height:45,
margin: const EdgeInsets.only(top: 10.0),
child:
RaisedButton(
color: Colors.green,
textColor: Colors.white,
padding: EdgeInsets.fromLTRB(9, 9, 9, 9),
child: Text('TIRAGE ALEATOIRE'),
onPressed: () {
Select_numbers();
},
),
),
Container(
width:300,
height:45,
margin: const EdgeInsets.only(top: 10.0),
child:
RaisedButton(
color: Colors.green,
textColor: Colors.white,
padding: EdgeInsets.fromLTRB(9, 9, 9, 9),
child: Text('VALIDER VOTRE GRILLE'),
onPressed: () {
Valide_grille();
},
),
),
]
)
),
),
);
}
getWidget() {
if (no_select.length==0) {
return Text("Pas de numéros");
}
else {
return GridView.count(
crossAxisCount: 5,
padding: const EdgeInsets.all(10.0),
mainAxisSpacing: 4.0,
crossAxisSpacing: 4.0,
children: new List<Widget>.generate(no_select.length, (index) {
return ClipOval(
child: Container(
color: Colors.red,
height: 20.0,
width: 20.0,
child: Center(
child: new Text((no_select[index].toString()),
style: TextStyle(color: Colors.white, fontSize: 24),
textAlign: TextAlign.center),
),
),
);
}
)
);
}
}
Select_numbers() {
setState(() {
var j = 1;
var num_sel;
var pos_sel;
no_select=[];
colorList=[];
colorList=List<Color>.generate(49, (int index) => Colors.lightBlue);
var rng = new Random();
List tab=[];
tab = List.generate(49, (int index) => index + 1);
print (tab);
while (j <= no_a_select) {
pos_sel = rng.nextInt(tab.length-1);
num_sel=tab[pos_sel];
no_select.add(num_sel);
colorList[num_sel-1] = Colors.redAccent;
tab.remove(num_sel);
print(tab);
j++;
}
print(no_select);
});
}
Future Valide_grille() async{
// For CircularProgressIndicator.
bool visible = false ;
// Showing CircularProgressIndicator.
setState(() {
visible = true ;
});
// SERVER LOGIN API URL
var url = 'https://www.easytrafic.fr/game_app/valide_lotto.php';
// Store all data with Param Name.
var data = {'id_membre':globals.id_membre, 'result':no_select};
print (data);
var grille_encode=jsonEncode(data);
print(grille_encode);
// Starting Web API Call.
var response = await http.post(url, body: grille_encode,headers: {'content-type': 'application/json','accept': 'application/json','authorization': globals.token});
print(response.body);
// Getting Server response into variable.
var message = json.decode(response.body);
// If the Response Message is Matched.
if(message == 'OK')
{
print('VALIDATION DE LA GRILLE OK');
// Hiding the CircularProgressIndicator.
setState(() {
visible = false;
});
}else{
// Hiding the CircularProgressIndicator.
setState(() {
visible = false;
});
// Showing Alert Dialog with Response JSON Message.
showDialog(
context: context,
builder: (BuildContext context) {
return AlertDialog(
title: new Text(message),
actions: <Widget>[
FlatButton(
child: new Text("OK"),
onPressed: () {
Navigator.of(context).pop();
},
),
],
);
},
);
}
}
}