update image list: mark termin 1 done, fix ascii/grayscale prompts

IMAGE_LIST.md

@@ -26,56 +26,57 @@ This document lists all images needed for the lecture slides. Each image include
 
 ## Termin 1: Grundlagen, Text & Audio
 
-### ⬚ matrix-code.png
-- **Context**: Opening visual for "Mysterium" hex dump slide
+### ✅ matrix-code.png
+- **Context**: Opening visual for "WTF!?" hex dump slide
 - **AI Prompt**: Matrix-style green digital rain code falling on black background, glowing green characters, cyberpunk hacker aesthetic, mysterious data visualization
 
-### ⬚ lightbulb-onoff.png
+### ✅ lightbulb-onoff.png
 - **Context**: Explaining the bit concept (0 or 1, on or off)
 - **AI Prompt**: Simple lightbulb comparison: one lit bright yellow, one dark/off, side by side, clean minimal style, binary concept visualization, white background
 
-### ⬚ grayscale-gradient.png
+### ✅ grayscale-gradient.png ⚠️ NEEDS REGENERATION
 - **Context**: Explaining 256 grayscale values (0=black to 255=white)
-- **AI Prompt**: Smooth horizontal grayscale gradient from pure black on left to pure white on right, demonstrating 256 shades, clean minimal style, technical demonstration
+- **AI Prompt**: Horizontal grayscale gradient bar on a neutral gray background (#808080), gradient goes from pure black (left) to pure white (right), add visible value labels "0" on left and "255" on right, ensure edges are clearly visible against background, clean educational diagram style, 16:9 aspect ratio
+- **Issue**: Current image has barely visible edges on left (black) and right (white) sides
 
-### ⬚ rgb-color-model.png
+### ✅ rgb-color-model.png
 - **Context**: Explaining RGB color model (3 bytes per pixel)
 - **AI Prompt**: RGB color model visualization showing three overlapping circles (red, green, blue) creating cyan, magenta, yellow, and white in overlaps, clean educational diagram style
 
-### ⬚ ascii-table.png
-- **Context**: Showing ASCII character encoding
-- **AI Prompt**: Clean ASCII table showing characters 0-127 with their decimal and hex values, vintage computer terminal aesthetic, green on black or clean white background, educational reference chart
+### ✅ ascii-table.png
+- **Context**: Showing ASCII character encoding (7-bit, 128 characters total)
+- **AI Prompt**: Clean ASCII table showing printable characters 32-126 with their decimal and hex values, vintage computer terminal aesthetic, green on black or clean white background, educational reference chart. Note: ASCII is 7-bit encoding with 128 total characters (0-127), not 256. First 32 (0-31) are control characters, 127 is DEL.
 
-### ⬚ hex-binary-table.png
+### ✅ hex-binary-table.png
 - **Context**: Hex to binary conversion reference
 - **AI Prompt**: Clean conversion table showing hexadecimal digits 0-F with their 4-bit binary equivalents, educational reference style, programmer cheat sheet aesthetic
 
-### ⬚ hexeditor-screenshot.png
+### ✅ hexeditor-screenshot.png
 - **Context**: Showing what a hex editor looks like
 - **AI Prompt**: Screenshot of hex editor software showing file bytes in hexadecimal with ASCII representation on the right side, typical hex editor layout, technical software interface
 
-### ⬚ cassette-ipod.png
+### ✅ cassette-ipod.png
 - **Context**: Audio format evolution intro
 - **AI Prompt**: Vintage audio cassette tape next to modern iPod or MP3 player, technology evolution comparison, nostalgic meets modern, clean product photography style
 
-### ⬚ compression-types.png
+### ✅ compression-types.png
 - **Context**: Lossless vs lossy compression comparison
 - **AI Prompt**: Split diagram comparing lossless (ZIP icon, identical files) vs lossy (JPEG/MP3 icon, smaller but different), educational infographic style, clear visual distinction
 
-### ⬚ karlheinz-brandenburg.jpg
-- **Context**: MP3 inventor portrait/reference
+### ✅ karlheinz-brandenburg.jpg
+- **Context**: MP3 inventor portrait/reference (Fraunhofer IIS)
 - **AI Prompt**: Professional portrait style of a German scientist/engineer in academic setting, Fraunhofer institute aesthetic, 1990s technology pioneer look (or use real photo)
 
-### ⬚ suzanne-vega.jpg
-- **Context**: "Tom's Diner" - the song used to test MP3
+### ✅ suzanne-vega.jpg
+- **Context**: "Tom's Diner" - the song used to test MP3 compression
 - **AI Prompt**: Female singer-songwriter aesthetic, acoustic guitar, 1980s folk music style, intimate cafe performance setting (or use real photo)
 
-### ⬚ audio-spectrogram.png
-- **Context**: Visualizing audio frequencies
+### ✅ audio-spectrogram.png
+- **Context**: Visualizing audio frequencies and MP3 compression effects
 - **AI Prompt**: Colorful audio spectrogram visualization showing frequency spectrum over time, rainbow gradient from low (red) to high (blue) frequencies, scientific audio analysis display
 
-### ⬚ napster-interface.png
-- **Context**: MP3 piracy era / file sharing history
+### ✅ napster-interface.png
+- **Context**: MP3 piracy era / file sharing history (1999-2001)
 - **AI Prompt**: Late 1990s peer-to-peer file sharing interface aesthetic, Windows 98/2000 style dialog boxes, music file listings, nostalgic internet era, retro software UI
 
 ---
@@ -301,11 +302,13 @@ This document lists all images needed for the lecture slides. Each image include
 | Lecture | Total | ✅ Done | ⬚ Todo |
 |---------|-------|--------|--------|
 | Intro | 1 | 1 | 0 |
-| Termin 1 (Grundlagen/Text/Audio) | 13 | 0 | 13 |
+| Termin 1 (Grundlagen/Text/Audio) | 13 | 13 | 0 |
 | Termin 2 (Bild/Audio/Video) | 10 | 10 | 0 |
 | Termin 3 (Speichermedien) | 16 | 0 | 16 |
 | Termin 4 (Distribution/APIs) | 25 | 0 | 25 |
-| **Total** | **65** | **11** | **54** |
+| **Total** | **65** | **24** | **41** |
+
+**Note:** grayscale-gradient.png is marked ⚠️ NEEDS REGENERATION due to visibility issues at edges.
 
 ## Generation Tips