// ServeTile returns a tile with appropriate Content-Type set.
func (d *Data) ServeTile(uuid dvid.UUID, ctx storage.Context, w http.ResponseWriter,
r *http.Request, parts []string) error {
if d.Levels == nil || len(d.Levels) == 0 {
return ErrNoMetadataSet
}
tileReq, err := d.parseTileReq(r, parts)
queryValues := r.URL.Query()
noblanksStr := dvid.InstanceName(queryValues.Get("noblanks"))
var noblanks bool
if noblanksStr == "true" {
noblanks = true
}
var formatStr string
if len(parts) >= 8 {
formatStr = parts[7]
}
data, err := d.getTileData(ctx, tileReq)
if err != nil {
server.BadRequest(w, r, err)
return err
}
if data == nil {
if noblanks {
http.NotFound(w, r)
return nil
}
img, err := d.getBlankTileImage(uuid, tileReq)
if err != nil {
return err
}
return dvid.WriteImageHttp(w, img, formatStr)
}
switch d.Encoding {
case LZ4:
var img dvid.Image
if err := img.Deserialize(data); err != nil {
return err
}
data, err = img.GetPNG()
w.Header().Set("Content-type", "image/png")
case PNG:
w.Header().Set("Content-type", "image/png")
case JPG:
w.Header().Set("Content-type", "image/jpeg")
}
if err != nil {
server.BadRequest(w, r, err)
return err
}
if _, err = w.Write(data); err != nil {
return err
}
return nil
}
// getTileImage returns a 2d tile image or a placeholder, useful for further stitching before
// delivery of a final image.
func (d *Data) getTileImage(ctx storage.Context, req TileReq) (image.Image, error) {
if d.Levels == nil || len(d.Levels) == 0 {
return nil, ErrNoMetadataSet
}
data, err := d.getTileData(ctx, req)
if err != nil {
return nil, err
}
if len(data) == 0 {
if d.Placeholder {
if req.scale < 0 || req.scale >= Scaling(len(d.Levels)) {
return nil, fmt.Errorf("Could not find tile specification at given scale %d", req.scale)
}
message := fmt.Sprintf("%s Tile coord %s @ scale %d", req.plane, req.tile, req.scale)
return dvid.PlaceholderImage(req.plane, d.Levels[req.scale].TileSize, message)
}
return nil, nil // Not found
}
var goImg image.Image
switch d.Encoding {
case LZ4:
var img dvid.Image
err = img.Deserialize(data)
if err != nil {
return nil, err
}
goImg = img.Get()
case PNG:
pngBuffer := bytes.NewBuffer(data)
goImg, err = png.Decode(pngBuffer)
case JPG:
jpgBuffer := bytes.NewBuffer(data)
goImg, err = jpeg.Decode(jpgBuffer)
default:
return nil, fmt.Errorf("Unknown tile encoding: %s", d.Encoding)
}
return goImg, err
}
// GetTile returns a 2d tile image or a placeholder
func (d *Data) GetTile(ctx storage.Context, shape dvid.DataShape, scaling Scaling, index dvid.IndexZYX) (image.Image, error) {
data, err := d.getTileData(ctx, shape, scaling, index)
if err != nil {
return nil, err
}
tileIndex := &IndexTile{&index, shape, scaling}
if data == nil {
if d.Placeholder {
if d.Levels == nil || scaling < 0 || scaling >= Scaling(len(d.Levels)) {
return nil, fmt.Errorf("Could not find tile specification at given scale %d", scaling)
}
message := fmt.Sprintf("%s Tile coord %s @ scale %d", shape, tileIndex, scaling)
return dvid.PlaceholderImage(shape, d.Levels[scaling].TileSize, message)
}
return nil, nil // Not found
}
var goImg image.Image
switch d.Encoding {
case LZ4:
var img dvid.Image
err = img.Deserialize(data)
if err != nil {
return nil, err
}
goImg = img.Get()
case PNG:
pngBuffer := bytes.NewBuffer(data)
goImg, err = png.Decode(pngBuffer)
case JPG:
jpgBuffer := bytes.NewBuffer(data)
goImg, err = jpeg.Decode(jpgBuffer)
default:
return nil, fmt.Errorf("Unknown tile encoding: %s", d.Encoding)
}
return goImg, err
}
// ServeTile returns a tile with appropriate Content-Type set.
func (d *Data) ServeTile(uuid dvid.UUID, ctx storage.Context, w http.ResponseWriter,
r *http.Request, parts []string) error {
if len(parts) < 7 {
return fmt.Errorf("'tile' request must be following by plane, scale level, and tile coordinate")
}
planeStr, scalingStr, coordStr := parts[4], parts[5], parts[6]
queryValues := r.URL.Query()
noblanksStr := dvid.InstanceName(queryValues.Get("noblanks"))
var noblanks bool
if noblanksStr == "true" {
noblanks = true
}
var formatStr string
if len(parts) >= 8 {
formatStr = parts[7]
}
// Construct the index for this tile
plane := dvid.DataShapeString(planeStr)
shape, err := plane.DataShape()
if err != nil {
err = fmt.Errorf("Illegal tile plane: %s (%v)", planeStr, err)
server.BadRequest(w, r, err)
return err
}
scaling, err := strconv.ParseUint(scalingStr, 10, 8)
if err != nil {
err = fmt.Errorf("Illegal tile scale: %s (%v)", scalingStr, err)
server.BadRequest(w, r, err)
return err
}
tileCoord, err := dvid.StringToPoint(coordStr, "_")
if err != nil {
err = fmt.Errorf("Illegal tile coordinate: %s (%v)", coordStr, err)
server.BadRequest(w, r, err)
return err
}
if tileCoord.NumDims() != 3 {
err = fmt.Errorf("Expected 3d tile coordinate, got %s", coordStr)
server.BadRequest(w, r, err)
return err
}
indexZYX := dvid.IndexZYX{tileCoord.Value(0), tileCoord.Value(1), tileCoord.Value(2)}
data, err := d.getTileData(ctx, shape, Scaling(scaling), indexZYX)
if err != nil {
server.BadRequest(w, r, err)
return err
}
if data == nil {
if noblanks {
http.NotFound(w, r)
return nil
}
img, err := d.getBlankTileImage(uuid, shape, Scaling(scaling))
if err != nil {
return err
}
return dvid.WriteImageHttp(w, img, formatStr)
}
switch d.Encoding {
case LZ4:
var img dvid.Image
if err := img.Deserialize(data); err != nil {
return err
}
data, err = img.GetPNG()
w.Header().Set("Content-type", "image/png")
case PNG:
w.Header().Set("Content-type", "image/png")
case JPG:
w.Header().Set("Content-type", "image/jpeg")
}
if err != nil {
server.BadRequest(w, r, err)
return err
}
if _, err = w.Write(data); err != nil {
return err
}
return nil
}