Class VideoWriterBuilder

java.lang.Object
com.codename1.media.VideoWriterBuilder
public class VideoWriterBuilder extends Object

A fluent builder describing how a video file should be encoded. It mirrors the style of MediaRecorderBuilder but covers the full set of knobs needed for video: dimensions, frame rate, codec, bitrate and key frame (GOP) interval, plus the audio track parameters. Build a VideoWriter with #build() and then push frames and audio into it.

Example:

VideoWriter w = new VideoWriterBuilder()
        .path(FileSystemStorage.getInstance().getAppHomePath() + "/out.mp4")
        .width(720).height(1280).frameRate(30)
        .videoCodec(VideoIO.CODEC_H264).videoBitRate(4_000_000)
        .hasAudio(true).audioCodec(VideoIO.CODEC_AAC).sampleRate(44100).audioChannels(2)
        .build();

  • Constructor Details

    • VideoWriterBuilder

      public VideoWriterBuilder()

  • Method Details

    • path

      public VideoWriterBuilder path(String path)

      Sets the output path where the encoded video will be written, as a com.codename1.io.FileSystemStorage path. Required.

      Parameters
      • path: the output FileSystemStorage path
      Returns

      Self for chaining.

    • container

      public VideoWriterBuilder container(String container)

      Sets the container format, e.g. VideoIO#CONTAINER_MP4 (default) or VideoIO#CONTAINER_WEBM.

      Returns

      Self for chaining.

    • hasVideo

      public VideoWriterBuilder hasVideo(boolean hasVideo)

      Enables or disables the video track. Defaults to true. Set to false to produce an audio only file.

      Returns

      Self for chaining.

    • width

      public VideoWriterBuilder width(int width)

      Sets the frame width in pixels. Default 1280.

      Returns

      Self for chaining.

    • height

      public VideoWriterBuilder height(int height)

      Sets the frame height in pixels. Default 720.

      Returns

      Self for chaining.

    • frameRate

      public VideoWriterBuilder frameRate(float frameRate)

      Sets the constant target frame rate in frames per second. Default 30. Frames are timestamped by the application when calling VideoWriter#writeFrame, this value is the nominal rate written into the file metadata and used by encoders that need it.

      Returns

      Self for chaining.

    • videoCodec

      public VideoWriterBuilder videoCodec(String videoCodec)

      Sets the video codec by id, e.g. VideoIO#CODEC_H264 (default). Use VideoIO#getAvailableEncoders() to discover what the platform supports.

      Returns

      Self for chaining.

    • videoBitRate

      public VideoWriterBuilder videoBitRate(int videoBitRate)

      Sets the target video bitrate in bits per second. When left at the default (-1) the implementation picks a reasonable value derived from the resolution and frame rate.

      Returns

      Self for chaining.

    • keyFrameInterval

      public VideoWriterBuilder keyFrameInterval(float seconds)

      Sets the key frame (GOP) interval in seconds. A smaller value produces files that seek more accurately at the cost of size. Default 2 seconds.

      Returns

      Self for chaining.

    • hasAudio

      public VideoWriterBuilder hasAudio(boolean hasAudio)

      Enables or disables the audio track. Defaults to false. When enabled, push PCM samples with VideoWriter#writeAudio.

      Returns

      Self for chaining.

    • audioCodec

      public VideoWriterBuilder audioCodec(String audioCodec)

      Sets the audio codec by id, e.g. VideoIO#CODEC_AAC (default).

      Returns

      Self for chaining.

    • audioBitRate

      public VideoWriterBuilder audioBitRate(int audioBitRate)

      Sets the target audio bitrate in bits per second. Default 128000.

      Returns

      Self for chaining.

    • sampleRate

      public VideoWriterBuilder sampleRate(int sampleRate)

      Sets the audio sample rate in Hz. Default 44100.

      Returns

      Self for chaining.

    • audioChannels

      public VideoWriterBuilder audioChannels(int audioChannels)

      Sets the number of audio channels. Default 2.

      Returns

      Self for chaining.

    • build

      public VideoWriter build() throws IOException

      Builds the VideoWriter with the current settings.

      Throws

      • IOException: if the writer could not be created

      • IllegalStateException: if #path(String) was not set or video encoding is not supported on this platform

      Throws:
      IOException

    • getPath

      public String getPath()
      The configured output path.

    • getContainer

      public String getContainer()
      The configured container format.

    • isHasVideo

      public boolean isHasVideo()
      True if the video track is enabled.

    • getWidth

      public int getWidth()
      The configured frame width.

    • getHeight

      public int getHeight()
      The configured frame height.

    • getFrameRate

      public float getFrameRate()
      The configured frame rate.

    • getVideoCodec

      public String getVideoCodec()
      The configured video codec id.

    • getVideoBitRate

      public int getVideoBitRate()
      The configured video bitrate, or -1 to let the implementation choose.

    • getKeyFrameInterval

      public float getKeyFrameInterval()
      The configured key frame interval in seconds.

    • isHasAudio

      public boolean isHasAudio()
      True if the audio track is enabled.

    • getAudioCodec

      public String getAudioCodec()
      The configured audio codec id.

    • getAudioBitRate

      public int getAudioBitRate()
      The configured audio bitrate.

    • getSampleRate

      public int getSampleRate()
      The configured audio sample rate.

    • getAudioChannels

      public int getAudioChannels()
      The configured audio channel count.