imaadpcm - npm Package Compare versions

Comparing version 1.0.4 to 1.1.0

index.js

@@ -83,4 +83,3 @@ /*!
         encoderPredicted = -0x8000;
-    }
-    else if (encoderPredicted > 0x7fff) {
+    } else if (encoderPredicted > 0x7fff) {
         encoderPredicted = 0x7fff;
@@ -91,4 +90,3 @@ }
         encoderIndex = 0;
-    }
-    else if (encoderIndex > 88) {
+    } else if (encoderIndex > 88) {
         encoderIndex = 88;
@@ -100,41 +98,2 @@ }
 /**
- * Return the head of a ADPCM sample block.
- * @param {number} sample The first sample of the block.
- * @return {!Array<number>}
- */
-function blockHead(sample) {
-    encodeSample(sample);
-    let adpcmSamples = [];
-    adpcmSamples.push(byteData.pack(sample, int16)[0]);
-    adpcmSamples.push(byteData.pack(sample, int16)[1]);
-    adpcmSamples.push(encoderIndex);
-    adpcmSamples.push(0);
-    return adpcmSamples;
-}
-
-/**
- * Encode a block of 505 16-bit samples as 4-bit ADPCM samples.
- * @param {!Array<number>} block A sample block of 505 samples.
- * @return {!Array<number>}
- */
-function encodeBlock(block) {
-    let adpcmSamples = blockHead(block[0]);
-    let x = 0;
-    for (let i=1; i<block.length; i++) {
-        x++;
-        if (x == 1) {
-            let sample2 = encodeSample(block[i]);
-            let sample = encodeSample(block[i + 1]);
-            adpcmSamples.push((sample << 4) | sample2);
-        } else {
-            x = 0;
-        }
-    }
-    while (adpcmSamples.length < 256) {
-        adpcmSamples.push(0);
-    }
-    return adpcmSamples;
-}
-
-/**
  * Decode a 4-bit ADPCM sample into a 16-bit PCM sample.
@@ -176,2 +135,35 @@ * @param {number} nibble A 4-bit adpcm sample.
 /**
+ * Return the head of a ADPCM sample block.
+ * @param {number} sample The first sample of the block.
+ * @return {!Array<number>}
+ */
+function blockHead(sample) {
+    encodeSample(sample);
+    let adpcmSamples = [];
+    adpcmSamples.push(byteData.pack(sample, int16)[0]);
+    adpcmSamples.push(byteData.pack(sample, int16)[1]);
+    adpcmSamples.push(encoderIndex);
+    adpcmSamples.push(0);
+    return adpcmSamples;
+}
+
+/**
+ * Encode a block of 505 16-bit samples as 4-bit ADPCM samples.
+ * @param {!Array<number>} block A sample block of 505 samples.
+ * @return {!Array<number>}
+ */
+function encodeBlock(block) {
+    let adpcmSamples = blockHead(block[0]);
+    for (let i=3; i<block.length; i+=2) {
+        let sample2 = encodeSample(block[i]);
+        let sample = encodeSample(block[i + 1]);
+        adpcmSamples.push((sample << 4) | sample2);
+    }
+    while (adpcmSamples.length < 256) {
+        adpcmSamples.push(0);
+    }
+    return adpcmSamples;
+}
+
+/**
  * Decode a block of 256 ADPCM samples into 16-bit PCM samples.
@@ -185,3 +177,6 @@ * @param {!Array<number>} block A adpcm sample block of 256 samples.
     decoderStep = stepTable[decoderIndex];
-    let result = [decoderPredicted];
+    let result = [
+            decoderPredicted,
+            byteData.unpack([block[2], block[3]], int16)
+        ];
     for (let i=4; i<block.length; i++) {
@@ -205,11 +200,7 @@ let original_sample = block[i];
     let block = [];
-    let x = 0;
-    for (let i=0;i<samples.length;i++) {
-        if (x < 505) {
-            block.push(samples[i]);
-            x++;
-        } else {
+    for (let i=0; i<samples.length; i++) {
+        block.push(samples[i]);
+        if ((i % 505 == 0 && i != 0) || i == samples.length - 1) {
             adpcmSamples = adpcmSamples.concat(encodeBlock(block));
             block = [];
-            x = 0;
         }
@@ -229,12 +220,8 @@ }
     let block = [];
-    let x = 0;
     for (let i=0; i<adpcmSamples.length; i++) {
-        if (x < blockAlign - 1) {
-            block.push(adpcmSamples[i]);
-            x++;
-        } else {
+        if (i % blockAlign == 0 && i != 0) {            
             samples = samples.concat(decodeBlock(block));
             block = [];
-            x = 0;
         }
+        block.push(adpcmSamples[i]);
     }
@@ -241,0 +228,0 @@ return samples;

package.json

 {
   "name": "imaadpcm",
-  "version": "1.0.4",
+  "version": "1.1.0",
   "description": "JavaScript IMA ADPCM codec.",
@@ -13,3 +13,5 @@ "homepage": "https://github.com/rochars/imaadpcm",
     "audio",
-    "codec"
+    "codec",
+    "encode",
+    "decode"
   ],
@@ -16,0 +18,0 @@ "repository": {

No alert changes

Worsened metrics

Total package byte prevSize

126888

decreased by-0.07%

Lines of code

2250

decreased by-0.57%

No dependency changes