diff --git a/ESP32_AP-Flasher/src/makeimage.cpp b/ESP32_AP-Flasher/src/makeimage.cpp
index caebf706..92332869 100644
--- a/ESP32_AP-Flasher/src/makeimage.cpp
+++ b/ESP32_AP-Flasher/src/makeimage.cpp
@@ -408,6 +408,11 @@ void spr2buffer(TFT_eSprite &spr, String &fileout, imgParam &imageParams) {
                 rewriteHeader(f_out);
             } else if (imageParams.g5) {
                 // handling for G5-compressed image data
+
+                uint8_t headerbuf[6];
+                prepareHeader(headerbuf, bufw, bufh, imageParams, buffer_size);
+                f_out.write(headerbuf, sizeof(headerbuf));
+
                 uint16_t height = imageParams.height;  // spr.height();
                 uint16_t width = imageParams.width;
                 spr.width();
@@ -446,11 +451,12 @@ void spr2buffer(TFT_eSprite &spr, String &fileout, imgParam &imageParams) {
                     printf("Compressed %d to %d bytes\n", buffer_size, outbufferSize);
                     if (outbufferSize > buffer_size) {
                         printf("That wasn't very useful, falling back to raw\n");
-                        free(outBuffer);
                         compressionSuccessful = false;
+                        f_out.seek(0);
                     } else {
                         f_out.write(outBuffer, outbufferSize);
                     }
+                    free(outBuffer);
                 }
                 if (!compressionSuccessful) {
                     // if we failed to compress the image, or the resulting image was larger than a raw file, fallback
diff --git a/ESP32_AP-Flasher/wwwroot/g5decoder.js b/ESP32_AP-Flasher/wwwroot/g5decoder.js
index e1146f16..f54cdf4a 100644
--- a/ESP32_AP-Flasher/wwwroot/g5decoder.js
+++ b/ESP32_AP-Flasher/wwwroot/g5decoder.js
@@ -143,8 +143,6 @@ function G5DrawLine(pPage, pCurFlips, pOut) {
         let visibleX = Math.max(0, startX);
         let visibleRun = Math.min(xright, startX + run) - visibleX;
 
-        if (pPage.y > 580) console.log("line " + visibleX + "-" + visibleRun);
-
         if (visibleRun > 0) {
             const startByte = visibleX >> 3;
             const endByte = (visibleX + visibleRun) >> 3;
@@ -221,13 +219,10 @@ function DecodeLine(pPage) {
         if (ulBitOff > (REGISTER_WIDTH - 8)) {
             pBufIndex += (ulBitOff >> 3);
             ulBitOff &= 7;
-            if (pPage.y > 580) console.log("ix: " + pBufIndex + " bit " + ulBitOff);
             ulBits = TIFFMOTOLONG(pBuf, pBufIndex);
         }
-        if (pPage.y > 580) console.log(ulBits.toString(2).padStart(32, '0') + " offset " + ulBitOff);
 
         if (((ulBits << ulBitOff) & 0x80000000) !== 0) {
-            if (pPage.y > 580) console.log("1> a0: " + pRef[pRefIndex] + " prefindex " + pRefIndex);
             a0 = pRef[pRefIndex++];
             pCur[pCurIndex++] = a0;
             ulBitOff++;
@@ -235,22 +230,17 @@ function DecodeLine(pPage) {
             const lBits = (ulBits >> (REGISTER_WIDTH - 8 - ulBitOff)) & 0xfe;
             const sCode = code_table[lBits];
             ulBitOff += code_table[lBits + 1];
-            if (pPage.y > 580) console.log("s: " + sCode);
             switch (sCode) {
                 case 1: case 2: case 3: // V(-1), V(-2), V(-3)
                     a0 = pRef[pRefIndex] - sCode;  // A0 = B1 - x
-                    if (pPage.y > 580) console.log("01> a0: " + pRef[pRefIndex] + " scode " + sCode + " prefindex " + pRefIndex);
                     pCur[pCurIndex++] = a0;
                     if (pRefIndex == 0) {
                         pRefIndex += 2;
-                        if (pPage.y > 580) console.log("01>   =0  new prefindex " + pRefIndex);
                     }
                     pRefIndex--;
                     while (a0 >= pRef[pRefIndex]) {
                         pRefIndex += 2;
-                        if (pPage.y > 580) console.log("01>   >=  new prefindex " + pRefIndex);
                     }
-                    if (pPage.y > 580) console.log("01>     new prefindex " + pRefIndex);
                     break;
 
                 case 0x11: case 0x12: case 0x13: // V(1), V(2), V(3)
@@ -313,7 +303,6 @@ function DecodeLine(pPage) {
                             ulBitOff += u32HLen;
                             break;
                     }
-                    if (pPage.y > 580) console.log("H: " + tot_run + " - " + tot_run1);
                     a0 = a0_p + tot_run;
                     pCur[pCurIndex++] = a0;
                     a0 += tot_run1;
@@ -332,7 +321,6 @@ function DecodeLine(pPage) {
                     break;
 
                 default: // ERROR
-                    console.log("scode " + sCode);
                     pPage.iError = G5_DECODE_ERROR;
                     return pPage.iError;
                     break;
@@ -365,7 +353,6 @@ function processG5(data, width, height) {
         let outputBuffer = new Uint8Array(height * ((width + 7) >> 3)); // Adjust for byte alignment
 
         for (let y = 0; y < height; y++) {
-            console.log(y + "    " + decoder.pBufIndex + "   " + data.length);
             let lineBuffer = outputBuffer.subarray(y * ((width + 7) >> 3), (y + 1) * ((width + 7) >> 3));
             decoder.y = y;
             let decodeResult = DecodeLine(decoder);
@@ -374,14 +361,12 @@ function processG5(data, width, height) {
                 console.log("Decoding error on line " + y + ": " + decoder.iError);
             }
 
-            if (y > 580) console.log("draw line " + y);
             G5DrawLine(decoder, decoder.pCur, lineBuffer);
             const temp = decoder.pRef;
             decoder.pRef = decoder.pCur;
             decoder.pCur = temp;
         }
 
-        console.log("Decoding complete.");
         return outputBuffer;
     } catch (error) {
         console.error("Error during G5 decoding:", error.message);
diff --git a/ESP32_AP-Flasher/wwwroot/main.js b/ESP32_AP-Flasher/wwwroot/main.js
index 86a2510b..ce2b9aae 100644
--- a/ESP32_AP-Flasher/wwwroot/main.js
+++ b/ESP32_AP-Flasher/wwwroot/main.js
@@ -1208,9 +1208,14 @@ function drawCanvas(buffer, canvas, hwtype, tagmac, doRotate) {
 		data = processZlib(data);
 	}
 	if (data.length > 0 && tagTypes[hwtype].g5 > 0 && $('#tag' + tagmac).dataset.ver >= tagTypes[hwtype].g5) {
-		console.log("calling G5 decoder");
-		console.log(tagTypes[hwtype].width);
-		data = processG5(data, tagTypes[hwtype].height, tagTypes[hwtype].width * 2);
+		const headerSize = data[0];
+		let bufw = (data[2] << 8) | data[1];
+		let bufh = (data[4] << 8) | data[3];
+		if ((bufw == tagTypes[hwtype].width || bufw == tagTypes[hwtype].height) && (bufh == tagTypes[hwtype].width || bufh == tagTypes[hwtype].height) && (data[5] <= 3)) {
+			// valid header for g5 compression
+			if (data[5] == 2) bufh *= 2;
+			data = processG5(data.subarray(headerSize), bufw, bufh);
+		}
 	}
 
 	[canvas.width, canvas.height] = [tagTypes[hwtype].width, tagTypes[hwtype].height] || [0, 0];