Quelle  IconUtil.java

package ch.threema.app.utils;

import android.content.ContentResolver;
import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.Point;
import android.media.MediaMetadataRetriever;
import android.media.ThumbnailUtils;
import android.net.Uri;
import android.os.Build;
import android.os.CancellationSignal;
import android.provider.DocumentsContract;
import android.provider.MediaStore;

import androidx.annotation.DrawableRes;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.WorkerThread;

import org.slf4j.Logger;

import java.io.IOException;

import ch.threema.app.R;
import ch.threema.app.ui.MediaItem;
import static ch.threema.base.utils.LoggingKt.getThreemaLogger;

import static android.media.MediaMetadataRetriever.OPTION_CLOSEST_SYNC;
import static ch.threema.app.services.MessageServiceImpl.THUMBNAIL_SIZE_PX;

public class IconUtil {
    private static final Logger logger = getThreemaLogger("IconUtil");

    public static @DrawableRes int getMimeCategoryIcon(MimeUtil.MimeCategory category) {
        switch (category) {
            case APK:
                return R.drawable.ic_doc_apk;
            case AUDIO:
                return R.drawable.ic_doc_audio;
            case CERTIFICATE:
                return R.drawable.ic_doc_certificate;
            case CODES:
                return R.drawable.ic_doc_codes;
            case COMPRESSED:
                return R.drawable.ic_doc_compressed;
            case CONTACT:
                return R.drawable.ic_doc_contact;
            case DOCUMENT:
                return R.drawable.ic_doc_document;
            case EVENT:
                return R.drawable.ic_doc_event;
            case FOLDER:
                return R.drawable.ic_doc_folder;
            case FONT:
                return R.drawable.ic_doc_font;
            case IMAGE:
                return R.drawable.ic_doc_image;
            case PDF:
                return R.drawable.ic_doc_pdf;
            case PRESENTATION:
                return R.drawable.ic_doc_presentation;
            case SPREADSHEET:
                return R.drawable.ic_doc_spreadsheet;
            case TEXT:
                return R.drawable.ic_doc_text;
            case VIDEO:
                return R.drawable.ic_doc_video;
            case WORD:
                return R.drawable.ic_doc_word;
            case EXCEL:
                return R.drawable.ic_doc_excel;
            case POWERPOINT:
                return R.drawable.ic_doc_powerpoint;
            default:
                return R.drawable.ic_doc_file;
        }
    }

    public static @DrawableRes int getMimeIcon(@Nullable String mimeType) {
        MimeUtil.MimeCategory category = MimeUtil.getMimeCategory(mimeType);
        return getMimeCategoryIcon(category);
    }

    @WorkerThread
    public static @Nullable Bitmap getThumbnailFromUri(Context context, Uri uri, int thumbSize, String mimeType, boolean ignoreExifRotate) {
        logger.debug("getThumbnailFromUri");

        String docId = null;
        long imageId = -1;
        Bitmap thumbnailBitmap = null;
        ContentResolver contentResolver = context.getContentResolver();
        BitmapUtil.ExifOrientation exifOrientation = BitmapUtil.getExifOrientation(context, uri);

        if (!MimeUtil.MIME_TYPE_IMAGE_JPEG.equals(mimeType) && !MimeUtil.MIME_TYPE_IMAGE_PNG.equals(mimeType) && !MimeUtil.MIME_TYPE_IMAGE_HEIF.equals(mimeType) && !MimeUtil.MIME_TYPE_IMAGE_HEIC.equals(mimeType)) {
            if (DocumentsContract.isDocumentUri(context, uri)) {
                // Note: these thumbnails MAY or MAY NOT have EXIF rotation already applied. So we can't use them for JPEG
                Point thumbPoint = new Point(thumbSize, thumbSize);
                try {
                    thumbnailBitmap = DocumentsContract.getDocumentThumbnail(contentResolver, uri, thumbPoint, new CancellationSignal());
                    if (thumbnailBitmap != null) {
                        return thumbnailBitmap;
                    }
                } catch (Exception e) {
                    // ignore - no thumbnail found
                    logger.error("Exception", e);
                }

                // get id from document provider
                docId = DocumentsContract.getDocumentId(uri);
            } else if (ContentResolver.SCHEME_CONTENT.equalsIgnoreCase(uri.getScheme())) {
                docId = uri.getLastPathSegment();
            }

            if (!TestUtil.isEmptyOrNull(docId)) {
                final String[] split = docId.split(":");
                if (split.length >= 2) {
                    final String idString = split[1];

                    if (!TestUtil.isEmptyOrNull(idString)) {
                        try {
                            imageId = Long.parseLong(idString);
                        } catch (NumberFormatException x) {
                            logger.error("Exception", x);
                        }
                    }
                }
            }

            if (imageId == -1) {
                // query media store for thumbnail
                String[] columns = new String[]{MediaStore.Images.Thumbnails._ID};
                try (Cursor cursor = contentResolver.query(uri, columns, null, null, null)) {

                    if (cursor != null && cursor.moveToFirst()) {
                        imageId = cursor.getInt(cursor.getColumnIndex(MediaStore.Images.Thumbnails._ID));
                    }
                } catch (Exception e) {
                    logger.error("Exception", e);
                }
            }

            logger.debug("Thumbnail image id: {}", imageId);

            if (imageId > 0) {
                // may throw java.lang.SecurityException
                try {
                    thumbnailBitmap = MediaStore.Images.Thumbnails.getThumbnail(contentResolver, imageId, MediaStore.Images.Thumbnails.MINI_KIND, null);
                } catch (Exception e) {
                    logger.error("Exception", e);
                }
            }
        }

        if (thumbnailBitmap == null) {
            // PNGs or GIFs may contain transparency
            boolean mayContainTransparency = MimeUtil.MIME_TYPE_IMAGE_PNG.equals(mimeType) || MimeUtil.MIME_TYPE_IMAGE_GIF.equals(mimeType);
            thumbnailBitmap = BitmapUtil.safeGetBitmapFromUri(context, uri, thumbSize, !mayContainTransparency, true, false);
        }

        if (thumbnailBitmap == null && MimeUtil.isVideoFile(mimeType)) {
            thumbnailBitmap = getVideoThumbnailFromUri(context, uri);

            if (thumbnailBitmap == null) {
                String path = FileUtil.getRealPathFromURI(context, uri);

                if (path != null) {
                    thumbnailBitmap = ThumbnailUtils.createVideoThumbnail(
                        path,
                        MediaStore.Images.Thumbnails.MINI_KIND);
                }
            }
        }

        if (thumbnailBitmap != null && !ignoreExifRotate && (exifOrientation.getRotation() != 0f || exifOrientation.getFlip() != BitmapUtil.FLIP_NONE)) {
            return BitmapUtil.rotateBitmap(thumbnailBitmap, exifOrientation.getRotation(), exifOrientation.getFlip());
        }

        return thumbnailBitmap;
    }

    @Nullable
    public static Bitmap getVideoThumbnailFromUri(@NonNull Context context, @NonNull Uri uri) {
        // TODO(ANDR-4279): Improve thumbnail extraction
        // do not use automatic resource management on MediaMetadataRetriever
        // noinspection resource
        final MediaMetadataRetriever retriever = new MediaMetadataRetriever();
        try {
            retriever.setDataSource(context, uri);
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1) {
                return retriever.getScaledFrameAtTime(1, OPTION_CLOSEST_SYNC, THUMBNAIL_SIZE_PX, THUMBNAIL_SIZE_PX);
            } else {
                final @Nullable Bitmap firstFrame = retriever.getFrameAtTime(1);
                if (firstFrame == null) {
                    logger.error("Failed to get first frame for video thumbnail");
                    return null;
                }
                return BitmapUtil.resizeBitmapExactlyToMaxWidth(firstFrame, THUMBNAIL_SIZE_PX);
            }
        } catch (Exception e) {
            //do not show the exception!
            logger.error("Exception", e);
        } finally {
            try {
                retriever.release();
            } catch (IOException e) {
                logger.debug("Failed to release MediaMetadataRetriever");
            }
        }
        return null;
    }

    @Nullable
    public static Bitmap getVideoThumbnailFromUri(@NonNull Context context, @NonNull MediaItem mediaItem) {
        // TODO(ANDR-4279): Improve thumbnail extraction
        // do not use automatic resource management on MediaMetadataRetriever
        // noinspection resource
        final MediaMetadataRetriever retriever = new MediaMetadataRetriever();
        try {
            retriever.setDataSource(context, mediaItem.getUri());
            final long timeUs = mediaItem.getStartTimeMs() == 0 ? 1L : mediaItem.getStartTimeMs() * 1000;
            final @Nullable Bitmap firstFrame = retriever.getFrameAtTime(timeUs);
            if (firstFrame == null) {
                logger.error("Failed to get first frame for video thumbnail");
                return null;
            }
            // getScaledFrameAtTime() returns unfiltered bitmaps that look bad at low resolutions
            return BitmapUtil.resizeBitmapExactlyToMaxWidth(firstFrame, THUMBNAIL_SIZE_PX);
        } catch (Exception e) {
            // do not show the exception!
            logger.error("Exception", e);
        } finally {
            try {
                retriever.release();
            } catch (IOException e) {
                logger.debug("Failed to release MediaMetadataRetriever");
            }
        }
        return null;
    }
}