still.go

// Copyright 2013, David Howden
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package raspicam

import (
	"time"
)

// DefaultRaspiStillCommand is the default command for capturing stills.
var DefaultRaspiStillCommand = "raspistill"

// DefaultRaspiStillYUVCommand is the default command for capturing YUV stills.
var DefaultRaspiStillYUVCommand = "raspiyuv"

// Encoding represents an enumeration of the supported encoding types.
type Encoding uint

const (
	EncodingJPEG Encoding = iota
	EncodingBMP
	EncodingGIF
	EncodingPNG
)

var encodings = [...]string{
	"jpg",
	"bmp",
	"gif",
	"png",
}

// String returns the parameter string for the given encoding.
func (s Encoding) String() string {
	return encodings[s]
}

// BaseStill represents the common elements between a Still and StillYUV
// as described in their equivalents found in RaspiStill.c and RaspiStillYUV.c
// respectively.
type BaseStill struct {
	CamSelect     int
	Timeout       time.Duration // Delay before image is taken
	Width, Height int           // Image dimensions
	Timelapse     int           // The number of pictures to take in the given timeout interval
	Camera        Camera
	Preview       Preview

	// The command to run when making a still capture.  If left blank, the default
	// command is used.
	Command string

	// Additional arguments.  Default is empty.
	Args []string
}

// The default BaseStill setup.
var defaultBaseStill = BaseStill{
	Timeout: 5 * time.Second,
	Width:   2592,
	Height:  1944,
	Camera:  defaultCamera,
	Preview: defaultPreview,
}

// String returns the parameter string for the given BaseStill.
func (s *BaseStill) String() string {
	return paramString(s)
}

func (s *BaseStill) params() []string {
	var out params
	out.add("--output", "-")
	if s.CamSelect != defaultStill.CamSelect {
		out.addInt("--camselect", s.CamSelect)
	}
	if s.Timeout != defaultStill.Timeout {
		out.addInt64("--timeout", int64(s.Timeout/time.Millisecond))
	}
	if s.Width != defaultStill.Width {
		out.addInt("--width", s.Width)
	}
	if s.Height != defaultStill.Height {
		out.addInt("--height", s.Height)
	}
	out.add(s.Camera.params()...)
	out.add(s.Preview.params()...)
	return out
}

// The default Still setup.
var defaultStill = Still{
	BaseStill: defaultBaseStill,
	Quality:   85,
	Encoding:  EncodingJPEG,
}

// Still represents the configuration necessary to call raspistill.
type Still struct {
	BaseStill
	Quality  int  // Quality (for lossy encoding)
	Raw      bool // Want a raw image?
	Encoding Encoding
}

// String returns the parameter string for the given Still struct.
func (s *Still) String() string {
	return paramString(s)
}

func (s *Still) params() []string {
	out := params(s.BaseStill.params())
	if s.Quality != defaultStill.Quality {
		out.addInt("--quality", s.Quality)
	}
	if s.Raw {
		out.add("--raw")
	}
	if s.Encoding != defaultStill.Encoding {
		out.add("--encoding", s.Encoding.String())
	}
	return out
}

// Cmd returns the raspicam command for a Still.
func (s *Still) Cmd() string {
	if s.BaseStill.Command != "" {
		return s.BaseStill.Command
	}
	return DefaultRaspiStillCommand
}

// Params returns the parameters to be used in the command execution.
func (s *Still) Params() []string {
	return append(s.params(), s.BaseStill.Args...)
}

// NewStill returns a *Still with the default values set by the raspistill command
// (see userland/linux/apps/raspicam/RaspiStill.c).
func NewStill() *Still {
	newStill := defaultStill
	return &newStill
}

// StillYUV represents the configuration necessary to call raspistillYUV.
type StillYUV struct {
	BaseStill
	UseRGB bool // Output RGB data rather than YUV
}

// The default StillYUV setup.
var defaultStillYUV = StillYUV{
	BaseStill: defaultBaseStill,
}

// String returns the parameter string for the given StillYUV struct.
func (s *StillYUV) String() string {
	return paramString(s)
}

func (s *StillYUV) params() []string {
	out := params(s.BaseStill.params())
	if s.UseRGB {
		out.add("--rgb")
	}
	return out
}

// Cmd returns the raspicam command for a StillYUV.
func (s *StillYUV) Cmd() string {
	if s.BaseStill.Command != "" {
		return s.BaseStill.Command
	}
	return DefaultRaspiStillYUVCommand
}

// Params returns the parameters to be used in the command execution.
func (s *StillYUV) Params() []string {
	return append(s.params(), s.BaseStill.Args...)
}

// NewStillYUV returns a *StillYUV with the default values set by the raspiyuv command
// (see userland/linux/apps/raspicam/RaspiStillYUV.c).
func NewStillYUV() *StillYUV {
	newStillYUV := defaultStillYUV
	return &newStillYUV
}