Blog Images

A retro-style 8-bit illustration features a computer screen with a visible code script. Surrounding it are symbolic representations of image generation: a markdown document, an image prompt morphing into abstract art, and a fading alt-text bubble. The design uses corporate colors, simple geometric shapes, and is limited to five colors, without including people or text.

Mar 23, 2025

 Generated by 🤖 AI 

We generate cover images to the blog, this in itself is completely uninteresting… but the script that generated the images is worth a look.

The generation of an blog post cover is done in 3 phases:

convert the blog markdown into an image prompt
generate an image from the image prompt
generate an alt text description from the image prompt
resize, copy image and patch the blog post frontmatter

script({ parameters: { force: false }, accept: ".md,.mdx" })
const file = env.files[0]
const target = path.changeext(file.filename, ".png")

const fm = MD.frontmatter(file.content)
if (env.vars.force || !(await workspace.stat(target))) {
    // phase 1: generate image prompt
    const style =
        "iconic, 2D, 8-bit, corporate, 5-color, simple, geometric, no people, no text"
    const { text: imagePrompt } = await runPrompt(
        (_) => {
            _.def("BLOG_POST", MD.content(file.content))
            _.$`Generate an image prompt for gpt-image-1 that illustrates the contents of <BLOG_POST>.
Include specific description related to the content of <BLOG_POST>.
    ${style}`
        },
        { responseType: "text", systemSafety: false }
    )

    // phase 2: generate image
    const image = await generateImage(
        `${imagePrompt}
    STYLE:
    ${style}`,
        {
            mime: "image/png",
            size: "landscape",
            maxHeight: 762,
            model: "openai:gpt-image-1",
        }
    )

    // phase 3: generate alt text
    const { text: alt } = await prompt`
Generate an alt text description from <IMAGE_PROMPT>.
Rephrase the prompt in a way that would be useful for someone who cannot see the image.
Do not start with "Alt Text:".

IMAGE_PROMPT:
${imagePrompt}`.options({
        responseType: "text",
        systemSafety: false,
        label: "alt-text",
    })

    // phase 4: patch frontmatter
    fm.cover = {
        alt,
        image: "./" + path.basename(target),
    }
    await workspace.copyFile(image.image.filename, target)
}

if (env.vars.force || !fm.tags?.length) {
    const res = await prompt`
Generate 5 keyword tags from <BLOG_POST>. The tags are used for SEO purposes in a blog.
Respond with 1 tag per line.

<BLOG_POST>
${MD.content(file.content)}
</BLOG_POST>`.options({
        responseType: "text",
        systemSafety: false,
        label: "tags",
    })
    if (!res.error)
        fm.tags = res.text
            ?.split(/\r?\n/g)
            .map((tag) => tag.trim())
            .filter(Boolean)
}

if (!fm.excerpt) {
    const res = await prompt`
Generate an excerpt from <BLOG_POST>.
- Do not use "Excerpt", "Unlock", "Master".
- Maximize engagement on LinkedIn. Your tone is friendly and technical.
- Do not be excited.
- Do not add code snippets or sections.

<BLOG_POST>
${MD.content(file.content)}
</BLOG_POST>`.options({
        responseType: "text",
        systemSafety: false,
        label: "excerpt",
    })
    if (!res.error) fm.excerpt = res.text.trim()
}

// phase 5: save files
file.content = MD.updateFrontmatter(file.content, fm)
await workspace.writeFiles(file)

Once this script worked for a couple posts, use used the convert command to generate the images for all the blog posts.

genaiscript convert blog-image blog/*.md*

What about the images?

The images are somewhat abstract, but they are generated from the blog post content. The image prompt could definitely be improved, but it’s a good start.