Hi Steffan and welcome to our :)

1. What version of Umbraco are you using?
2. What does the code your using to fetch the images look like?
3. What is the type of image you're uploading? (.jpg,.jpeg,.png,.gif etc.)
4. What is the image size in terms of kb/mb?

/Jan

Hi Jan

1. Sorry, I lost the opening line when I copied across the draft of my post – Umbraco v6.0.6 (Assembly version: 1.0.4898.16909).
   
   
2. See below after the other answers...
   
   
3. I stupidly hadn't realised that all the affected images are PNGs – like I said the images have all been successfully uploaded and two of them used to render just fine though but now that I realise they're all PNGs I've tried substituting a JPG for one of them and it worked fine.
   
   
4. I am not sure how this could play into this as two of the images used to render, there are much larger images that still render (albeit JPEGs), and it's the markup that is missing – while the images requested directly by the src that should be generate appear with no problem). But in answer to your question: 36 KB, 51.5 KB, and 124.4 KB.

The problem (after further investigation) is with the block highlighted in red (in the third code block below) that aborts further processing if media.UmbracoFile is found to be Null or Empty.

Having checked cmsContentXml for all of the PNGs, they all have the appropriate umbracoFile node so I'm at a loss as to why the paths for these have suddenly stopped being processed at this point in their handling.

One affected page has the following template:

<%@ Master Language="C#" MasterPageFile="~/masterpages/Public.master" %>

<asp:content ContentPlaceHolderId="HeaderContent" runat="server">
    <h2><umbraco:Item field="headerText" stripParagraph="true" runat="server" /></h2>
</asp:content>
<asp:content ContentPlaceHolderId="MainContent" runat="server">
    <div class="row">
        <div class="span4">
            <umbraco:Macro Alias="DisplayImage" MediaId="[#bodyImage]" ImageWidth="340" runat="server" />
        </div>
        <div class="span4">
            <umbraco:Item Field="bodyText" runat="server" />
        </div>
    </div>
</asp:content>
<asp:content ContentPlaceHolderID="SideContent" runat="server">
    <umbraco:Macro Alias="LatestNews" runat="server" />
    <umbraco:Macro Alias="GetInTouch" runat="server" />
</asp:content>

With the highlighted Macro (DisplayImage.cshtml) being:

@*
    Paramaters:
    MediaId (mandatory)
    ImageWidth (int, mandatory)
    ImageHeight (optional)
    Constrain (optional. Only works if ImageHeight has been set)
    BgColor (optional. Only works if ImageHeight. Ignores the constrain and sets the the pad value to true
    AltText (optional, gets media name by default)
    ImageClass (optional, sets the css class to an image)
    FloatImage (bool, optional, floats the image)
*@
@using umbraco.MacroEngines
@inherits DynamicNodeContext
@{
    int mediaId;
    if (!int.TryParse(Parameter.MediaId, out mediaId))
    {
        return;
    }
    
    bool floatImage;
    bool.TryParse(Parameter.FloatImage, out floatImage);
    if (floatImage)
    {
        <div class="floatImage">
        @RenderPage("ResizeImage.cshtml", Parameter.MediaId, Parameter.ImageWidth, Parameter.ImageHeight, Parameter.Constrain, Parameter.BgColor, Parameter.AltText, Parameter.ImageClass)
        </div>
    }
    else
    {
        @RenderPage("ResizeImage.cshtml", Parameter.MediaId, Parameter.ImageWidth, Parameter.ImageHeight, Parameter.Constrain, Parameter.BgColor, Parameter.AltText, Parameter.ImageClass)
    }
}

Which in turn calls (ResizeImage.cshtml):

@*
    Paramaters:
    MediaId (mandatory)
    ImageWidth (mandatory)
    ImageHeight (optional)
    Constrain (optional. Only works if ImageHeight has been set)
    BgColor (optional. Only works if ImageHeight. Ignores the constrain and sets the the pad value to true
    AltText (optional, gets media name by default)
    ImageClass (optional, sets the css class to an image)
*@

@using System.Collections.Specialized
@using Bootstrap.Logic.Utils
@using umbraco.MacroEngines
@inherits DynamicNodeContext
@{
    int mediaId;
    if(!int.TryParse(PageData[0], out mediaId))
    {
        return;
    }
    
    var nvc = new NameValueCollection();
    var media = Library.MediaById(mediaId);
    if (media == null || media.NodeTypeAlias != "Image")
    {
        return;
    }
        
    string mediaPath = media.UmbracoFile;
    if (string.IsNullOrEmpty(mediaPath))
    {
        return;
    }
    
    int mediaWidth =  int.Parse(media.UmbracoWidth.ToString());
    int mediaHeight = int.Parse(media.UmbracoHeight.ToString());
    int newWidth = int.Parse(PageData[1]);
    int newHeight;
    if (newWidth < mediaWidth)
    {
        newHeight = newWidth * mediaHeight / mediaWidth;
    }
    else
    {
        newWidth = mediaWidth;
        newHeight = mediaHeight;
    }
    int maxHeight;
    if (int.TryParse(PageData[2], out maxHeight))
    {
        bool constrain;
        if (bool.TryParse(PageData[3], out constrain))
        {
            if (constrain)
            {
                nvc.Add("constrain", "true");
                if (newHeight > maxHeight)
                {
                    newWidth = maxHeight * mediaWidth / mediaHeight;
                    newHeight = maxHeight;
                }
            }
            else
            {
                nvc.Add("constrain", "false");
                newWidth = int.Parse(PageData[1]);
                newHeight = int.Parse(PageData[2]);
            }
        }

        if(!string.IsNullOrEmpty(PageData[4]))
        {
            // Ignore constrain 
            newWidth = int.Parse(PageData[1]);
            newHeight = int.Parse(PageData[2]);
            nvc.Remove("constrain");
            nvc.Add("pad", "true");
            nvc.Add("bgcolor", PageData[4]);
        }

        nvc.Add("width", newWidth.ToString());
        nvc.Add("height", newHeight.ToString());
    }
    else
    {
        nvc.Add("width", newWidth.ToString());
    }
        
    var query = nvc.ConstructQueryString();

    string mediaName = string.IsNullOrEmpty(PageData[5]) ? media.Name : PageData[5];
    string imageClass = !string.IsNullOrEmpty(PageData[6]) ? string.Format(" class=\"{0}\"", PageData[6]) : string.Empty;
    <img src="/ImageGen.ashx?image=@mediaPath&amp;@query" width="@newWidth" height="@newHeight" alt="@mediaName"@Html.Raw(imageClass) />
}

No point going as far as the code for ImageGen.ashx as (as already pointed out) the images load just fine when access via the address bar and it's the actual markup that's missing (for PNGs only, though only since Monday) and because the umbracoFile details are not being read for PNGs.

Thanks in advance for any help you can offer.

Sorry, didn't realise the code would get parsed and styled and thereby lose the styling I'd added.

The problem occurs when the third file reaches this block:

    string mediaPath = media.UmbracoFile;
    if(string.IsNullOrEmpty(mediaPath))
    {
        return;
    }

Hi Steffan

Sorry for the late reply - Happy that you found the soltuon and thanks for sharing :)

/Jan

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