Page image export

PNG and SVG export the engine's final positioned pages, including tables, charts, barcodes, images, headers and footers. They are page pictures, not editable report projects or data exports. Generate first; Studio exports the last generated request even if the editors contain unfinished changes. As with PDF/HTML, export renders that saved request again, so nondeterministic trusted scripts can produce new values. Save the project separately to preserve template and source data.

Studio

1. Generate preview, then open Preview → Export images.
2. Choose PNG or SVG. PNG offers 72, 150 (default) or 300 DPI. Higher DPI creates more pixels; it does not change page breaks or wrap text again. SVG is vector and disables the DPI selector.
3. Choose All pages, Current page or Page range. Current uses the viewer's selected page at dialog opening; range endpoints are inclusive and start at 1.
4. Leave Always package as ZIP checked for an archive. Uncheck it for a single selected page to download one PNG/SVG. Multiple pages always produce ZIP.
5. Download and inspect the result. ZIP entries retain original page numbers: page-0002.png, page-0003.png, etc. Cancel leaves the report unchanged.

The page background is opaque white. SVG embeds raster images and converts text into vector outlines using the same regular/bold DejaVu fonts as the report. It needs no installed fonts or network resources. Text is not selectable or searchable in PNG/SVG; use PDF or HTML when text search/accessibility is needed. SVG retains physical dimensions in points plus a matching viewBox. Raster PNG stores its DPI in pHYs metadata; consumers may choose their own print scaling.

PNG dimensions are ceil(page points × DPI / 72). A4 portrait (595.28 × 841.89pt) is 1241 × 1754px at 150 DPI. For barcode scanning, prefer 150–300 DPI and adequate module width: a one-pixel module at 72 DPI may require magnification by a detector. Neither resolution settings nor successful software decoding prove physical printer/scanner behavior. Raster edges can differ slightly from browser/PDF antialiasing; layout coordinates and embedded font outlines are retained.

Limits: 72–300 DPI, at most 100 selected pages, 25 million pixels per PNG page, 100 million pixels per PNG export, 25 MB per SVG and 100 MB ZIP. Lower DPI or select a smaller page range when a limit is reached. Export finishes in memory before writing the destination; rejected options do not create partial files. Large exports use native raster memory in addition to the output buffer.

CLI

With local Studio running:

# All pages, ZIP containing PNG files at 150 DPI
python3 scripts/report-tool.py --template samples/sales.nrtemplate \
  --data samples/sales.data.json --parameters samples/sales.parameters.json \
  --format png --output artifacts/sales-pages.zip

# One vector page, standalone SVG
python3 scripts/report-tool.py --template samples/circular-charts.nrtemplate \
  --data samples/circular-charts.data.json --format svg \
  --first-page 1 --last-page 1 --single-image --output artifacts/composition.svg

Use --dpi 300 for high-resolution PNG and --first-page/--last-page for a range. --single-image disables forced ZIP only when exactly one page is selected. The output suffix must match the actual response (.zip, .png or .svg). Omit --output to validate export without saving it. report-tool.py requires Studio.

The standalone .NET CLI also recognizes .png/.svg for a one-page report and .png.zip/.svg.zip for a whole report (default 150 DPI):

dotnet run --project src/NextgenReports.Cli -c Release -- \
  samples/circular-charts.nrtemplate samples/circular-charts.data.json \
  artifacts/composition.png

A multipage report with a single-image suffix fails before writing the file; use an archive suffix or select pages through report-tool.py. Existing PDF/HTML CLI behavior remains available.

API and .NET

POST /api/export/images accepts the same template/data/parameters as /api/preview, plus optional options:

{
  "template": {},
  "data": {},
  "options": {
    "format": "png",
    "dpi": 150,
    "firstPage": 1,
    "lastPage": 2,
    "archive": true
  }
}

Defaults: png, 150 DPI, first page 1, last page equal to the report's page count, archive true. The result is application/zip, image/png or image/svg+xml with Content-Disposition and X-Report-Pages (number of exported pages). Validation errors return HTTP 400 Problem Details, including parameterErrors where relevant. The existing same-origin rules apply. Scripts follow the host's opt-in setting.

.NET callers pass a calculated ReportDocument to PageImageExporter.Export with PageImageOptions. It returns media type, extension and exported page count. SVG uses outlined text; no third-party SVG parser is used. SkiaSharp and Linux native assets are pinned to 3.119.2, with their upstream notices shipped under licenses/. Local Linux on iMac is verified; macOS/Windows remain unverified.