I have created a chart with excel 2007 and am trying to export it with Chart.ToImage(). The output file quality is nowhere close to the detail of the chart in the spreadsheet, x-values don't fit correctly, etc...Is this component supposed to accurately render the chart as it appears in the worksheet itself?

I am using version 4.6 of Aspose.Cells for .Net.

Hi,

 

Thank you for considering Aspose.

 

Please share your template file and code, so we can figure out the issue you are having.

 

Thank You & Best Regards,

---

Nausherwan Aslam
Support Developer,
Aspose Sialkot Team
Contact Us

VB.NET CODE:

 Dim workbook As New Workbook()
workbook.Open("c:\myTemplate.xlsx")
Dim worksheet As Worksheet = workbook.Worksheets(0)
Dim chart As Chart = worksheet.Charts(0)
Dim bitmap As System.Drawing.Bitmap = chart.ToImage()
bitmap.Save("c:\test.jpg", ImageFormat.Jpeg)
       

Oh, and here is the resulting jpeg...

Hi,

 

Thank you for sharing the template file and sample code. We have found the issue you mentioned (in Excel 2007 file format) after an initial test. We will fix it and get back to you soon.

 

Thank You & Best Regards,

---

Nausherwan Aslam
Support Developer,
Aspose Sialkot Team
Contact Us

If I save the template as an Excel 2003 workbook and run the code again, I get something better but the text and lines are very jaggy...at least compared to how the chart shows up in real excel.

test.jpg is using Chart.ToImage(). fromExcel.PNG is how it looks in Excel.

EDIT: It looks like your rendering engine does not antialias the drawn lines in your line charts. It looks like you are just using System.Drawing.Graphics (?) which makes this ridiculously easy with Graphics.SmoothingMode...

Hi,

Thank you for sharing further information.We are looking into your issue and we will get back to you soon.

Thank you for your patience,

---

Nausherwan Aslam
Support Developer,
Aspose Sialkot Team
Contact Us

There are a couple more fairly serious problems:

1. The line colors are way off. In the spreadsheet I provided, the chart's series have the colors:
Series 1: (51,131,151)
Series 2: (127,127,127)

Aspose renders this as:
Series 1: (51, 153,102)
Series 2: (128,128,128)

2. The rendered line markers are sized too small. I can fix this with a little code pretty easily (always up the marker size by 2 or so), but if you look at the image I have attached, which is how Excel exports its own chart (using VBA), you can see that they make the line markers much larger than you guys do. This may be due to the antialiasing that the VBA engine does to the lines...not sure.

Hi,

 

Thank for all your feedback, currently we are not supporting the Excel 2007 chart to Image conversion in Aspose.Cells. Our schedule is to start this feature’s development form the next month. We will try to support all of you mentioned issues and we will appreciate if you can provide us with the list of chart types which you are using, so we can provide you with your required features at the earliest.

 

Thank you for understanding,

---

Nausherwan Aslam
Support Developer,
Aspose Sialkot Team
Contact Us

Is your development for Excel 2007 on track for being released in the near future? We have a new requirement that we cannot even use compatibility mode for our new spreadsheets (which we HAVE to develop in Excel 2007).

Hi,

Thank you for considering Aspose.

We are working on this feature and we will release the Chart2Image feature for Excel 2007 file format soon.

Thank you for understanding,

---

Nausherwan Aslam
Support Developer,
Aspose Sialkot Team
Contact Us

Hi,

 

Thank you for considering Aspose.

 

Following is the complete schedule for this feature (Chart2Image for Excel 2007).

 

1: Development Started in Feb 2009.

2: Development Scheduled to complete on 30^th April 2009.

3: After testing the release is scheduled on 30^th May 2009.

 

Thank You & Best Regards,

---

Nausherwan Aslam
Support Developer,
Aspose Sialkot Team
Contact Us

Hello,

Has any progress been made in terms of the quality of the image itself that is being exported when using Chart.toImage? I have upgraded to Aspose.Cells version 4.7.1, but I haven't seen any increase in the quality of the charts from previous versions in terms of jagged lines.

I've attached my excel file and the resulting jpeg from export. As you can see, the line quality is drastically reduced from viewing the chart in Excel and the exported jpeg. I've tried using NSeries.Smooth = true and setting the jpeg quality to 100, but that doesn't have any effect.

Thanks,

Matt

Hi Matt,

 

Thank you for considering Aspose.

 

After an initial test we found your mentioned issue regarding image quality of generated Jpeg is not very good as compared to the excel chart. We will look into your issue and try to improve the image quality and get back to you soon.

 

Thank You & Best Regards,

---

Nausherwan Aslam
Support Developer,
Aspose Sialkot Team
Contact Us

Thank you very much for your responsiveness!