The first two articles have introduced FFmpeg for audio processing, audio and video processing: FFmpeg is used on the android side for audio mixing, splicing and cutting , and FFmpeg is used on the android side for audio and video synthesis and separation . For FFmpeg involving file import and cmake configuration, you can view the first article. Now let's discuss video related processing: video transcoding, video cutting, video screenshots, adding watermarks, video to Gif animations, and image synthesis video.
1. Video transcoding
Video transcoding includes format, bit rate, size and other conversions. -f represents forced conversion format, -b represents bit rate, -s represents size, and -r represents frame rate:
/**
* 使用ffmpeg命令行进行视频转码
* @param srcFile 源文件
* @param targetFile 目标文件（后缀指定转码格式）
* @return 转码后的文件
*/
public static String[] transformVideo(String srcFile, String targetFile){
String transformVideoCmd = "ffmpeg -i %s -r 25 -b 200 -s 1080x720 %s";
transformVideoCmd = String.format(transformVideoCmd, srcFile, targetFile);
return transformVideoCmd.split(" ");//以空格分割为字符串数组
}2. Video cutting
Video cutting is to cut the specified video from the specified start time of the video, -ss represents the start time, and -t represents the duration:
/**
* 使用ffmpeg命令行进行视频剪切
* @param srcFile 源文件
* @param startTime 剪切的开始时间(单位为秒)
* @param duration 剪切时长(单位为秒)
* @param targetFile 目标文件
* @return 剪切后的文件
*/
public static String[] cutVideo(String srcFile, int startTime, int duration, String targetFile){
String cutVideoCmd = "ffmpeg -i %s -ss %d -t %d %s";
cutVideoCmd = String.format(cutVideoCmd, srcFile, startTime, duration, targetFile);
return cutVideoCmd.split(" ");//以空格分割为字符串数组
}3. Video screenshot
Video screenshot is to capture the current frame from the video, save it as a picture in the specified format, and use the image2 tool:
/**
* 使用ffmpeg命令行进行视频截图
* @param srcFile 源文件
* @param size 图片尺寸大小
* @param targetFile 目标文件
* @return 截图后的文件
*/
public static String[] screenShot(String srcFile, String size, String targetFile){
String screenShotCmd = "ffmpeg -i %s -f image2 -t 0.001 -s %s %s";
screenShotCmd = String.format(screenShotCmd, srcFile, size, targetFile);
return screenShotCmd.split(" ");//以空格分割为字符串数组
}4. Add a watermark
Adding a watermark to a video includes: text and pictures, use the filter_complex filter, and overlay specifies the position of the picture in the video:
/**
* 使用ffmpeg命令行给视频添加水印
* @param srcFile 源文件
* @param waterMark 水印文件路径
* @param targetFile 目标文件
* @return 添加水印后的文件
*/
public static String[] addWaterMark(String srcFile, String waterMark, String targetFile){
String waterMarkCmd = "ffmpeg -i %s -i %s -filter_complex overlay=0:0 %s";
waterMarkCmd = String.format(waterMarkCmd, srcFile, waterMark, targetFile);
return waterMarkCmd.split(" ");//以空格分割为字符串数组
}
Adding text watermark is actually to convert text into image, which is finally added in the form of image. The process of converting text to image is as follows:
/**
* 文本转成Bitmap
* @param text 文本内容
* @param context 上下文
* @return 图片的bitmap
*/
private static Bitmap textToBitmap(String text , Context context) {
float scale = context.getResources().getDisplayMetrics().scaledDensity;
TextView tv = new TextView(context);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
tv.setLayoutParams(layoutParams);
tv.setText(text);
tv.setTextSize(scale * TEXT_SIZE);
tv.setGravity(Gravity.CENTER_HORIZONTAL);
tv.setDrawingCacheEnabled(true);
tv.setTextColor(TEXT_COLOR);
tv.setBackgroundColor(Color.WHITE);
tv.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
tv.layout(0, 0, tv.getMeasuredWidth(), tv.getMeasuredHeight());
tv.buildDrawingCache();
Bitmap bitmap = tv.getDrawingCache();
int rate = bitmap.getHeight() / 20;
return Bitmap.createScaledBitmap(bitmap, bitmap.getWidth()/rate, 20, false);
}
/**
* 文字生成图片
* @param filePath filePath
* @param text text
* @param context context
* @return 生成图片是否成功
*/
public static boolean textToPicture(String filePath, String text , Context context){
Bitmap bitmap = textToBitmap(text , context);
FileOutputStream outputStream = null;
try {
outputStream = new FileOutputStream(filePath);
bitmap.compress(Bitmap.CompressFormat.JPEG, 90, outputStream);
outputStream.flush();
} catch (IOException e) {
e.printStackTrace();
return false;
}finally {
try {
if(outputStream != null){
outputStream.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return true;
}
5. Video capture GIF animation
Take a picture from the video, save it in GIF format, use the GIF tool, use -ss to specify the start time, and -t to specify the duration of the interception:
/**
* 使用ffmpeg命令行进行视频转成Gif动图
* @param srcFile 源文件
* @param startTime 开始时间
* @param duration 截取时长
* @param targetFile 目标文件
* @return Gif文件
*/
public static String[] generateGif(String srcFile, int startTime, int duration, String targetFile){
//String screenShotCmd = "ffmpeg -i %s -vframes %d -f gif %s";
String screenShotCmd = "ffmpeg -i %s -ss %d -t %d -s 320x240 -f gif %s";
screenShotCmd = String.format(screenShotCmd, srcFile, startTime, duration, targetFile);
return screenShotCmd.split(" ");//以空格分割为字符串数组
}
6. Image synthesis video
Image synthesis video is to order the named pictures of the folder, use -image2 to synthesize the video, use -r to specify the frame rate, here is specified to play one frame per second:
/**
* 使用ffmpeg命令行进行图片合成视频
* @param srcFile 源文件
* @param targetFile 目标文件(mpg格式)
* @return 合成的视频文件
*/
public static String[] pictureToVideo(String srcFile, String targetFile){
//-f image2：代表使用image2格式，需要放在输入文件前面
String combineVideo = "ffmpeg -f image2 -r 1 -i %simg#d.jpg -vcodec mpeg4 %s";
combineVideo = String.format(combineVideo, srcFile, targetFile);
combineVideo = combineVideo.replace("#", "%");
Log.i("VideoHandleActivity", "combineVideo=" + combineVideo);
return combineVideo.split(" ");//以空格分割为字符串数组
}
After splicing the command line, call the native method of FFmpeg to process:
/**
* 调用ffmpeg处理视频
* @param handleType handleType
*/
private void doHandleVideo(int handleType){
String[] commandLine = null;
switch (handleType){
case 0://视频转码
String transformVideo = PATH + File.separator + "transformVideo.wmv";
commandLine = FFmpegUtil.transformVideo(srcFile, transformVideo);
break;
case 1://视频剪切
String cutVideo = PATH + File.separator + "cutVideo.mp4";
int startTime = 0;
int duration = 20;
commandLine = FFmpegUtil.cutVideo(srcFile, startTime, duration, cutVideo);
break;
case 2://视频合并
break;
case 3://视频截图
String screenShot = PATH + File.separator + "screenShot.jpg";
String size = "1080x720";
commandLine = FFmpegUtil.screenShot(srcFile, size, screenShot);
break;
case 4://视频添加水印
//1、图片
String photo = PATH + File.separator + "launcher.png";
String photoMark = PATH + File.separator + "photoMark.mp4";
commandLine = FFmpegUtil.addWaterMark(appendVideo, photo, photoMark);
//2、文字
//String text = "Hello,FFmpeg";
//String textPath = PATH + File.separator + "text.jpg";
//boolean result = BitmapUtil.textToPicture(textPath, text, this);
//Log.i(TAG, "text to pitcture result=" + result);
//String textMark = PATH + File.separator + "textMark.mp4";
//commandLine = FFmpegUtil.addWaterMark(appendVideo, photo, textMark);
break;
case 5://视频转成gif
String Video2Gif = PATH + File.separator + "Video2Gif.gif";
int gifStart = 30;
int gifDuration = 5;
commandLine = FFmpegUtil.generateGif(srcFile, gifStart, gifDuration, Video2Gif);
break;
case 6://屏幕录制
break;
case 7://图片合成视频
//图片所在路径，图片命名格式img+number.jpg
String picturePath = PATH + File.separator + "img/";
String combineVideo = PATH + File.separator + "combineVideo.mp4";
commandLine = FFmpegUtil.pictureToVideo(picturePath, combineVideo);
break;
default:
break;
}
executeFFmpegCmd(commandLine);
}
/**
* 执行ffmpeg命令行
* @param commandLine commandLine
*/
private void executeFFmpegCmd(final String[] commandLine){
if(commandLine == null){
return;
}
FFmpegCmd.execute(commandLine, new FFmpegCmd.OnHandleListener() {
@Override
public void onBegin() {
Log.i(TAG, "handle video onBegin...");
mHandler.obtainMessage(MSG_BEGIN).sendToTarget();
}
@Override
public void onEnd(int result) {
Log.i(TAG, "handle video onEnd...");
mHandler.obtainMessage(MSG_FINISH).sendToTarget();
}
});
}
JNIEXPORT jint JNICALL Java_com_frank_ffmpeg_FFmpegCmd_handle
(JNIEnv *env, jclass obj, jobjectArray commands){
int argc = (*env)->GetArrayLength(env, commands);
char **argv = (char**)malloc(argc * sizeof(char*));
int i;
int result;
for (i = 0; i < argc; i++) {
jstring jstr = (jstring) (*env)->GetObjectArrayElement(env, commands, i);
char* temp = (char*) (*env)->GetStringUTFChars(env, jstr, 0);
argv[i] = malloc(1024);
strcpy(argv[i], temp);
(*env)->ReleaseStringUTFChars(env, jstr, temp);
}
//执行ffmpeg命令
result = run(argc, argv);
//释放内存
for (i = 0; i < argc; i++) {
free(argv[i]);
}
free(argv);
return result;
}Well, the introduction of video cutting, transcoding, screenshots, adding watermarks, and capturing GIF images using FFmpeg is completed. If you have any questions or suggestions, welcome to communicate.
Source code: https://github.com/xufuji456/FFmpegAndroid . If it helps you, please fork and star.