我只是在我的C ++项目中使用与位图锁位的例子创建了一个新功能：
void GetFrameData(Bitmap ^b)
{
typedef System::Drawing::Rectangle R;
R rect = R(0,0,b->Width,b->Height);
System::Drawing::Imaging::BitmapData^ bmpData = b->LockBits( rect, System::Drawing::Imaging::ImageLockMode::ReadWrite, b->PixelFormat );
// Get the address of the first line.
IntPtr ptr = bmpData->Scan0;
// Declare an array to hold the bytes of the bitmap.
// This code is specific to a bitmap with 24 bits per pixels.
int bytes = Math::Abs(bmpData->Stride) * b->Height;
array<Byte>^rgbValues = gcnew array<Byte>(bytes);
// Copy the RGB values into the array.
System::Runtime::InteropServices::Marshal::Copy( ptr, rgbValues, 0, bytes );
// Set every third value to 255.
for ( int counter = 2; counter < rgbValues->Length; counter += 3 )
rgbValues[ counter ] = 255;
// Copy the RGB values back to the bitmap
System::Runtime::InteropServices::Marshal::Copy( rgbValues, 0, ptr, bytes );
// Unlock the bits.
b->UnlockBits( bmpData );
}
这个功能可以从CSHARP得到一个位图文件并不知我需要使用这个lockbits的像素从位图到这个功能复制：
void Encoder_start(char *filename)
{
printf("Encode video file %s\n", filename);
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
// f = fopen(filename, "wb");
errn = fopen_s(&f,filename, "wb");
if (!f) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
frame = avcodec_alloc_frame();
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
frame->format = c->pix_fmt;
frame->width = c->width;
frame->height = c->height;
/* the image can be allocated by any means and av_image_alloc() is
* just the most convenient way if av_malloc() is to be used */
// ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height,
// c->pix_fmt, 32);
frame->data[0] = (uint8_t*)av_malloc(1000000);
frame->data[1] = (uint8_t*)av_malloc(1000000);
frame->data[2] = (uint8_t*)av_malloc(1000000);
frame->data[3] = (uint8_t*)av_malloc(1000000);
frame->data[4] = (uint8_t*)av_malloc(1000000);
frame->data[5] = (uint8_t*)av_malloc(1000000);
frame->data[6] = (uint8_t*)av_malloc(1000000);
frame->data[7] = (uint8_t*)av_malloc(1000000);
if (frame->data[7]==0) {
//if (ret < 0) {
fprintf(stderr, "Could not allocate raw picture buffer\n");
exit(1);
}
total_frame_counter=0;
}
void Encoder_push_frame()
{
/* encode 1 second of video */
// for(i=0;i<25;i++) {
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
/* prepare a dummy image */
/* Y */
for(y=0;y<c->height;y++) {
for(x=0;x<c->width;x++) {
frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0;y<c->height/2;y++) {
for(x=0;x<c->width/2;x++) {
frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2;
frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5;
}
}
frame->pts = total_frame_counter;
total_frame_counter++;
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", total_frame_counter, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
// }
}
我不知道如何填写，并与什么av_malloc我将它设置为1000000测试每个地方。
而Encoder_push_frame功能应该得到的像素或者它与av_malloc的想法是填补push_frame功能将图像从位图像素的。
我尝试了很多方法，但它并没有在所有的工作。
编辑
我使用此代码：
void GetFrameData(Bitmap ^b)
{
auto bmpData = b->LockBits( System::Drawing::Rectangle(0,0,b->Width,b->Height), ImageLockMode::ReadWrite, PixelFormat::Format24bppRgb );
// The beginning of the bitmap data in memory
char* top = bmpData->Scan0.ToPointer();
// find bitmap data for the top row (if bottom-up bitmap, this is at the end)
if (bmpData->Stride < 0) {
top += Stride * (1 - b->Height);
}
for( int y = 0; y < b->Height; ++y ) {
RGBTRIPLE* row = (RGBTRIPLE*)(top + y * bmpData->Stride);
// saturate red channel
for( int x = 0; x < b->Width; ++x ) {
row[x].rgbtBlue = 255;
row[x].rgbtGreen = 255;
row[x].rgbtRed = 255;
}
// Unlock the bits.
b->UnlockBits( bmpData );
}
在矩形我不得不将其更改为：系统::绘图::矩形如果不是的话，我对矩形一个错误，它与另一矩形的冲突。 但经过现在改口了我对bmpData在这条线的错误：
char* top = bmpData->Scan0.ToPointer();
智能感知：类型的值“无效*”不能用于初始化类型“的char *”的一个实体
第二个错误是在跨越：
top += Stride * (1 - b->Height);
错误：智能感知：标识符“步幅”是未定义的
我怎样才能解决这个错误。
和：
改变的for循环：
for( int x = 0; x < b->Width; ++x ) {
row[x].rgbtBlue = 255;
row[x].rgbtGreen = 255;
row[x].rgbtRed = 255;
其原因我改变它是你没有行[X] .R = 255; 但R不存在/定义，因此我应该怎么在这对如何解决它呢？ （我想我所做的是错的）。
