Question

L.S。，

使用Delphi（Seattle）我已成功在FireMonkey应用程序中创建了一个绘图。我通过使用像

这样的语句来做到这一点

Image1.Bitmap.SaveToFile('AFilename.bmp');

最终的绘图在我的屏幕上看起来很完美，但是当我想要保存位图，然后我打开文件时，它总是显示为黑屏！为什么这样？

我使用了声明：

MPEG-2 Verification Sequence
akiyo_cif    /* name of source files */
-        /* name of reconstructed images ("-": don't store) */
-         /* name of intra quant matrix file     ("-": default matrix) */ 
-         /* name of non intra quant matrix file ("-": default matrix) */
-         /* name of statistics file ("-": stdout ) */
1         /* input picture file format: 0=*.Y,*.U,*.V, 1=*.yuv, 2=*.ppm */ 
300         /* number of frames */
0         /* number of first frame */
23:59:59:24 /* timecode of first frame */
6         /* N (# of frames in GOP) */
2         /* M (I/P frame distance) */
0         /* ISO/IEC 11172-2 stream */
0         /* 0:frame pictures, 1:field pictures */
352       /* horizontal_size */
288       /* vertical_size */
2         /* aspect_ratio_information 1=square pel, 2=4:3, 3=16:9, 4=2.11:1 */
3         /* frame_rate_code 2=23.976, 3=25, 4=29.97, 5=30 frames/second */
400000.0  /* bit_rate (bits/s) */
6         /* vbv_buffer_size (in multiples of 16 kbit) */
0         /* low_delay  */
0         /* constrained_parameters_flag */
4         /* Profile ID: Simple = 5, Main = 4, SNR = 3, Spatial = 2, High = 1 */
8         /* Level ID:   Low = 10, Main = 8, High 1440 = 6, High = 4          */
0         /* progressive_sequence */
1         /* chroma_format: 1=4:2:0, 2=4:2:2, 3=4:4:4 */
1         /* video_format: 0=comp., 1=PAL, 2=NTSC, 3=SECAM, 4=MAC, 5=unspec. */
5         /* color_primaries */
5         /* transfer_characteristics */
5         /* matrix_coefficients */
352       /* display_horizontal_size */
288       /* display_vertical_size */
1         /* intra_dc_precision (0: 8 bit, 1: 9 bit, 2: 10 bit, 3: 11 bit */
1         /* top_field_first */
1 0 0     /* frame_pred_frame_dct (I P B) */
0 0 0     /* concealment_motion_vectors (I P B) */
0 1 1     /* q_scale_type  (I P B) */
1 1 0     /* intra_vlc_format (I P B)*/
1 0 1     /* alternate_scan (I P B) */
0         /* repeat_first_field */
0         /* progressive_frame */
0         /* P distance between complete intra slice refresh */
0         /* rate control: r (reaction parameter) */
0         /* rate control: avg_act (initial average activity) */
0         /* rate control: Xi (initial I frame global complexity measure) */
0         /* rate control: Xp (initial P frame global complexity measure) */
0         /* rate control: Xb (initial B frame global complexity measure) */
0         /* rate control: d0i (initial I frame virtual buffer fullness) */
0         /* rate control: d0p (initial P frame virtual buffer fullness) */
0         /* rate control: d0b (initial B frame virtual buffer fullness) */
2 2 11 11 /* P:  forw_hor_f_code forw_vert_f_code search_width/height */
1 1 3  3  /* B1: forw_hor_f_code forw_vert_f_code search_width/height */
1 1 7  7  /* B1: back_hor_f_code back_vert_f_code search_width/height */
1 1 7  7  /* B2: forw_hor_f_code forw_vert_f_code search_width/height */
1 1 3  3  /* B2: back_hor_f_code back_vert_f_code search_width/height */

有人可以告诉我我需要做些什么才能做到正确吗？非常感谢。

扬

Answer 1

这对我有用：

procedure TForm1.Button1Click(Sender: TObject);
var
  path: TPathData;
begin
  path := TPathData.Create;
  path.MoveTo( PointF(10,10));
  path.lineto( PointF(20,20));
  path.AddEllipse(RectF(15,10,25,30));

  Image1.Bitmap := TBitmap.Create(50, 50);
  Image1.Bitmap.Canvas.BeginScene;
  Image1.Bitmap.Canvas.Clear(TAlphaColors.White);
  Image1.Bitmap.Canvas.Stroke.Color := TAlphaColors.Black;
  Image1.Bitmap.Canvas.StrokeThickness := 1;
  Image1.Bitmap.Canvas.DrawPath(path, 1);
  Image1.Bitmap.Canvas.EndScene;

  Image1.Bitmap.SaveToFile('C:\Users\me\Desktop\AFilename.png');
end;

Output AFilename.png

为什么“Bitmap.SaveToFile会导致黑屏

1 个答案: