diff --git a/app/src/main/java/app/fedilab/android/mastodon/helper/BlurHashDecoder.kt b/app/src/main/java/app/fedilab/android/mastodon/helper/BlurHashDecoder.kt new file mode 100644 index 00000000..e192239f --- /dev/null +++ b/app/src/main/java/app/fedilab/android/mastodon/helper/BlurHashDecoder.kt @@ -0,0 +1,127 @@ +package app.fedilab.android.mastodon.helper + + +import android.graphics.Bitmap +import android.graphics.Color +import kotlin.math.PI +import kotlin.math.cos +import kotlin.math.pow +import kotlin.math.withSign + +class BlurHashDecoder { + + fun decode(blurHash: String?, width: Int, height: Int, punch: Float = 1f): Bitmap? { + require(width > 0) { "Width must be greater than zero" } + require(height > 0) { "height must be greater than zero" } + if (blurHash == null || blurHash.length < 6) { + return null + } + val numCompEnc = decode83(blurHash, 0, 1) + val numCompX = (numCompEnc % 9) + 1 + val numCompY = (numCompEnc / 9) + 1 + if (blurHash.length != 4 + 2 * numCompX * numCompY) { + return null + } + val maxAcEnc = decode83(blurHash, 1, 2) + val maxAc = (maxAcEnc + 1) / 166f + val colors = Array(numCompX * numCompY) { i -> + if (i == 0) { + val colorEnc = decode83(blurHash, 2, 6) + decodeDc(colorEnc) + } else { + val from = 4 + i * 2 + val colorEnc = decode83(blurHash, from, from + 2) + decodeAc(colorEnc, maxAc * punch) + } + } + return composeBitmap(width, height, numCompX, numCompY, colors) + } + + private fun decode83(str: String, from: Int = 0, to: Int = str.length): Int { + var result = 0 + for (i in from until to) { + val index = charMap[str[i]] ?: -1 + if (index != -1) { + result = result * 83 + index + } + } + return result + } + + private fun decodeDc(colorEnc: Int): FloatArray { + val r = colorEnc shr 16 + val g = (colorEnc shr 8) and 255 + val b = colorEnc and 255 + return floatArrayOf(srgbToLinear(r), srgbToLinear(g), srgbToLinear(b)) + } + + private fun srgbToLinear(colorEnc: Int): Float { + val v = colorEnc / 255f + return if (v <= 0.04045f) { + (v / 12.92f) + } else { + ((v + 0.055f) / 1.055f).pow(2.4f) + } + } + + private fun decodeAc(value: Int, maxAc: Float): FloatArray { + val r = value / (19 * 19) + val g = (value / 19) % 19 + val b = value % 19 + return floatArrayOf( + signedPow2((r - 9) / 9.0f) * maxAc, + signedPow2((g - 9) / 9.0f) * maxAc, + signedPow2((b - 9) / 9.0f) * maxAc + ) + } + + private fun signedPow2(value: Float) = value.pow(2f).withSign(value) + + private fun composeBitmap( + width: Int, + height: Int, + numCompX: Int, + numCompY: Int, + colors: Array + ): Bitmap { + val imageArray = IntArray(width * height) + for (y in 0 until height) { + for (x in 0 until width) { + var r = 0f + var g = 0f + var b = 0f + for (j in 0 until numCompY) { + for (i in 0 until numCompX) { + val basis = (cos(PI * x * i / width) * cos(PI * y * j / height)).toFloat() + val color = colors[j * numCompX + i] + r += color[0] * basis + g += color[1] * basis + b += color[2] * basis + } + } + imageArray[x + width * y] = + Color.rgb(linearToSrgb(r), linearToSrgb(g), linearToSrgb(b)) + } + } + return Bitmap.createBitmap(imageArray, width, height, Bitmap.Config.ARGB_8888) + } + + private fun linearToSrgb(value: Float): Int { + val v = value.coerceIn(0f, 1f) + return if (v <= 0.0031308f) { + (v * 12.92f * 255f + 0.5f).toInt() + } else { + ((1.055f * v.pow(1 / 2.4f) - 0.055f) * 255 + 0.5f).toInt() + } + } + + private val charMap = listOf( + '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', + 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', + 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', + 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '#', '$', '%', '*', '+', ',', + '-', '.', ':', ';', '=', '?', '@', '[', ']', '^', '_', '{', '|', '}', '~' + ) + .mapIndexed { i, c -> c to i } + .toMap() +} \ No newline at end of file diff --git a/app/src/main/java/app/fedilab/android/mastodon/ui/drawer/StatusAdapter.java b/app/src/main/java/app/fedilab/android/mastodon/ui/drawer/StatusAdapter.java index 1353d368..7660beca 100644 --- a/app/src/main/java/app/fedilab/android/mastodon/ui/drawer/StatusAdapter.java +++ b/app/src/main/java/app/fedilab/android/mastodon/ui/drawer/StatusAdapter.java @@ -39,8 +39,10 @@ import android.content.Context; import android.content.Intent; import android.content.SharedPreferences; import android.content.res.Configuration; +import android.graphics.Bitmap; import android.graphics.PorterDuff; import android.graphics.Typeface; +import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.os.Build; import android.os.Bundle; @@ -138,6 +140,7 @@ import app.fedilab.android.mastodon.client.entities.app.StatusCache; import app.fedilab.android.mastodon.client.entities.app.StatusDraft; import app.fedilab.android.mastodon.client.entities.app.Timeline; import app.fedilab.android.mastodon.exception.DBException; +import app.fedilab.android.mastodon.helper.BlurHashDecoder; import app.fedilab.android.mastodon.helper.CrossActionHelper; import app.fedilab.android.mastodon.helper.GlideApp; import app.fedilab.android.mastodon.helper.GlideFocus; @@ -2211,13 +2214,24 @@ public class StatusAdapter extends RecyclerView.Adapter boolean expand_media = sharedpreferences.getBoolean(context.getString(R.string.SET_EXPAND_MEDIA), false); RequestBuilder requestBuilder; GlideRequests glideRequests = GlideApp.with(context); + Bitmap placeholder = null; + if (attachment.blurhash != null) { + placeholder = new BlurHashDecoder().decode(attachment.blurhash, 32, 32, 1f); + } if (!isSensitive || expand_media) { requestBuilder = glideRequests.asDrawable(); if (!fullAttachement) { + if (placeholder != null) { + requestBuilder = requestBuilder.placeholder(new BitmapDrawable(context.getResources(), placeholder)); + } requestBuilder = requestBuilder.apply(new RequestOptions().transform(new GlideFocus(focusX, focusY))); requestBuilder = requestBuilder.dontAnimate(); } else { - requestBuilder = requestBuilder.placeholder(R.color.transparent_grey); + if (placeholder != null) { + requestBuilder = requestBuilder.placeholder(new BitmapDrawable(context.getResources(), placeholder)); + } else { + requestBuilder = requestBuilder.placeholder(R.color.transparent_grey); + } requestBuilder = requestBuilder.dontAnimate(); requestBuilder = requestBuilder.apply(new RequestOptions().override((int) mediaW, (int) mediaH)); requestBuilder = requestBuilder.fitCenter();