Add .gitignore to exclude all node packages and lock files

skills/remotion-prompt-video/node_modules/@remotion/renderer/dist/get-extra-frames-to-capture.js

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+"use strict";
+// For seamless AAC concatenation, we need to capture a bit of extra audio on both sides
+// to later align the audio correctly. This function calculates the exact frames to capture.
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.getExtraFramesToCapture = void 0;
+const combine_audio_1 = require("./combine-audio");
+const sample_rate_1 = require("./sample-rate");
+// Inspired by https://github.com/wistia/seamless-aac-split-and-stitch-demo
+// We can seamlessly concatenate AAC files if we capture a bit of extra audio on both sides in each chunk and then align the audio correctly.
+// This function calculates which extra frames should be evaluated for their audio content.
+const getExtraFramesToCapture = ({ compositionStart, realFrameRange, fps, forSeamlessAacConcatenation, }) => {
+    // If the feature is disabled, don't capture extra frames.
+    if (!forSeamlessAacConcatenation) {
+        return {
+            extraFramesToCaptureAssetsBackend: [],
+            extraFramesToCaptureAssetsFrontend: [],
+            chunkLengthInSeconds: (realFrameRange[1] - realFrameRange[0] + 1) / fps,
+            trimLeftOffset: 0,
+            trimRightOffset: 0,
+        };
+    }
+    // If this video is just a chunk as part of a larger video,
+    // We also need to know the start time of this chunk to align it correctly.
+    const chunkStart = realFrameRange[0];
+    // If we are only rendering a portion of the composition, we also need to account for that.
+    // It cannot be that the chunk start time is earlier than the composition time.
+    if (chunkStart < compositionStart) {
+        throw new Error('chunkStart may not be below compositionStart');
+    }
+    const realLeftEnd = chunkStart - compositionStart;
+    if (realLeftEnd < 0) {
+        throw new Error('chunkStat - compositionStart may not be below 0');
+    }
+    const realRightEnd = realLeftEnd + (realFrameRange[1] - realFrameRange[0] + 1);
+    // Find the closest AAC packet border and add two AAC packet padding.
+    const aacAdjustedLeftEnd = Math.max(0, (0, combine_audio_1.getClosestAlignedTime)(realLeftEnd / fps) - 2 * (1024 / sample_rate_1.DEFAULT_SAMPLE_RATE));
+    const aacAdjustedRightEnd = (0, combine_audio_1.getClosestAlignedTime)(realRightEnd / fps) +
+        2 * (1024 / sample_rate_1.DEFAULT_SAMPLE_RATE);
+    // Now find the additional frames that we need to capture to have enough audio
+    const alignedStartFrameWithoutOffset = Math.floor(aacAdjustedLeftEnd * fps);
+    const alignedStartFrame = alignedStartFrameWithoutOffset + compositionStart;
+    const alignedEndFrame = Math.ceil(aacAdjustedRightEnd * fps) + compositionStart;
+    const extraFramesToCaptureAudioOnlyFrontend = new Array(realFrameRange[0] - alignedStartFrame)
+        .fill(true)
+        .map((_, f) => f + alignedStartFrame);
+    const extraFramesToCaptureAudioOnlyBackend = new Array(alignedEndFrame - realFrameRange[1] - 1)
+        .fill(true)
+        .map((_, f) => f + realFrameRange[1] + 1);
+    // But now, we might have too much audio, since the extra frames only have a `1 / fps` step.
+    // When creating the lossless audio for a chunk, we need to shave that extra audio off.
+    const trimLeftOffset = (aacAdjustedLeftEnd * fps - alignedStartFrameWithoutOffset) / fps;
+    const trimRightOffset = (aacAdjustedRightEnd * fps - Math.ceil(aacAdjustedRightEnd * fps)) / fps;
+    const chunkLengthInSeconds = aacAdjustedRightEnd - aacAdjustedLeftEnd;
+    return {
+        extraFramesToCaptureAssetsFrontend: extraFramesToCaptureAudioOnlyFrontend,
+        extraFramesToCaptureAssetsBackend: extraFramesToCaptureAudioOnlyBackend,
+        chunkLengthInSeconds,
+        trimLeftOffset,
+        trimRightOffset,
+    };
+};
+exports.getExtraFramesToCapture = getExtraFramesToCapture;