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FFmpeg HDR to SDR tone mapping that doesn't look washed out (2026)

TL;DR Converting HDR10 to SDR with a naive FFmpeg command gives you grey, washed-out video. The fix is tone mapping. We will detect HDR with ffprobe , run two working tone-map chains ( zscale on CPU, libplacebo on GPU) in FFmpeg 8.0, compare operators, and batch it. Test the commands on your own build before shipping. 📦 Code: github.com/USER/hdr-to-sdr, replace before publishing If you have ever run an HDR clip through your normal pipeline and gotten back something flat and foggy, this post is for you. The bug is that HDR and SDR are different color systems, and "just converting" reinterprets one as the other. We will use FFmpeg 8.0 "Huffman" (8.0.2 is current as of May 2026). Why naive conversion fails HDR10 SDR Transfer function PQ (SMPTE ST 2084) gamma 2.4 / BT.1886 Color primaries Rec.2020 (wide) BT.709 (narrow) Peak luminance ~1,000 to 4,000 nits ~100 nits A command that ends in -pix_fmt yuv420p with no tone mapping reads PQ-encoded, Rec.2020 values as if they were SDR. The gamut gets crushed with no intelligence and the brightness curve is misread. Hence the fog. 1. Detect whether a file is even HDR 🔍 Do not tone-map SDR files. Check first: # detect transfer characteristics and primaries ffprobe -v error -select_streams v:0 \ -show_entries stream = color_transfer,color_primaries,color_space \ -of default = noprint_wrappers = 1 input.mkv HDR10 content reports something like: color_space = bt2020nc color_transfer = smpte2084 color_primaries = bt2020 If color_transfer is smpte2084 (PQ) or arib-std-b67 (HLG), you have HDR and you need to tone-map. If it says bt709 , leave it alone. 2. The libplacebo path (GPU, my default) 🚀 libplacebo is the Vulkan-accelerated filter in FFmpeg 8.0. It follows the ITU tone-mapping recommendations and handles the color conversions internally, so the command is short: ffmpeg -i input.mkv \ -vf "libplacebo=tonemapping=bt.2390:colorspace=bt709:color_primaries=bt709:color_trc=bt709:format=yuv420p" \ -c :v libx264 -crf 20 -c :a copy \ ou

2026-07-06 原文 →
AI 资讯

I've Been Trying to Write AI Video Prompts for Months. They All Sucked Until I Found a Formula.

The Problem Nobody Talks About Everyone's posting AI-generated videos — characters speaking with lip-sync, manga panels coming alive, virtual idols dancing. The pitch: "just describe what you want." I tried. For months. Here's what I got: Character's face morphed by frame 2 "Slowly looks up" became "violent head shake" Voice-over sounded like Google Translate Same prompt, 3 runs, 3 completely different results No idea what to include or how long the prompt should be Tutorials were either too vague ("be detailed") or too technical (parameter tuning from line 1). The real issue: video prompts are structurally different from text/image prompts. You need to simultaneously control visuals, motion, audio, camera, and consistency constraints — in the right order, at the right length. What I Found A Skill in the Model Studio official repo called happyhorse-prompt-studio . It doesn't teach you theory — it asks you questions and assembles the prompt for you . 4-phase flow: 1. Inspiration Menu Shows you 4 "flavors" of what HappyHorse can do: Flavor What it does A · Voiced Manga Drama Characters talk to each other, with voice + lip-sync B · Character Voice PV Single character self-introduction, 8-10 sec C · Manga Panel Motion Static manga panel starts breathing D · Virtual Idol MV Idol performance with choreography 2. Discovery Asks you conversationally: character appearance, scene, emotion, dialogue, voice type, art style, camera. 3. Prompt Assembly Assembles using the HappyHorse Formula : Scene + Subject + Motion + Audio + Quality Key techniques: @「Image n」 syntax locks character identity across shots Dialogue ≤15 characters (split shots if longer) Japanese prompts work best (HappyHorse is JP-optimized) Always end with キャラの顔・髪・衣装が変わらない (face/hair/outfit stays unchanged) 4. Quality Check Auto-reviews: completeness, compliance, cost estimate, optimization tips. Before vs. After Dimension Writing myself With Prompt Studio Attempts needed 10-20 before one usable 2-3 to satisfacti

2026-07-06 原文 →
AI 资讯

Nano Banana 2 Lite and Gemini Omni Flash: What's Actually New in Google's Gemini API

Google added two new models to the Gemini API today: Nano Banana 2 Lite (image generation) and Gemini Omni Flash (video generation + editing). Neither is the Gemini 3.5 Pro release people have been waiting for, so it's easy to miss. Here's what's actually in them. TL;DR Nano Banana 2 Lite: gemini-3.1-flash-lite-image = text-to-image in ~4s, $0.034/1K images Gemini Omni Flash: gemini-omni-flash-preview = video gen + conversational editing, $0.10/sec Both are built to be chained: generate an image fast, then animate it into video Neither model is positioned as a quality upgrade = both are cost/speed plays Nano Banana 2 Lite Model ID: gemini-3.1-flash-lite-image Text-to-image output in about 4 seconds $0.034 per 1K-resolution image Positioned as the direct replacement for the original Nano Banana ( gemini-2.5-flash-image ) - if you're on that model, this is a drop-in upgrade Available in Google AI Studio, Gemini API, Gemini Enterprise Agent Platform, and consumer surfaces (Search AI Mode, Gemini app, Photos, NotebookLM, Flow, Google Ads) Gemini Omni Flash Model ID: gemini-omni-flash-preview Public preview in Google AI Studio and the Gemini API Conversational editing - refine a generated video using plain-language instructions instead of re-prompting from zero Multimodal referencing - combine text, image, and video inputs to keep a scene consistent $0.10 per second of video output (same rate as Veo 3.1 Fast) Known limitations right now Generations capped at 10 seconds No audio reference uploads yet No scene extension yet Video references under 3 seconds are accepted by the API schema but not correctly processed yet Character consistency across scene changes/pans still has rough edges Google says longer durations are coming. The part worth paying attention to: chaining them Generate an image with Nano Banana 2 Lite (fast, cheap) Pass that image as a reference into Omni Flash Omni Flash animates it into a video Both models are optimized for throughput and cost, not for to

2026-07-03 原文 →
AI 资讯

Turn the camera away, and the AI's world freezes

Video AI systems consistently fail to track what happens when the camera looks away: when a scene pans away from an object in motion and returns, current models re-render the object in its original position rather than showing the logical result of off-screen change. Scaling to more parameters makes this failure worse, not better, according to WRBench , a new benchmark that tests what researchers call "world model reliability." The benchmark presents AI video systems with scenes where something happens off-screen — the camera pans away while an object is in motion, or while a light changes, or while an open door should stay open — then pans back to see what the system believes should have happened. A system that genuinely models the world would track what occurred during the off-screen interval. Current systems mostly don't. Key facts What: A new benchmark tests whether video AI systems can track what happens to parts of a scene the camera isn't currently showing. Across 23 models, the answer is mostly no — and making the models larger made the problem worse, not better. When: 2026-06-19 Primary source: read the source (arXiv 2606.20545) The benchmark covers twenty-three different video generation models and nearly ten thousand video clips across six categories of off-screen change, each designed to test a different aspect of world continuity: objects in motion, light sources changing, object states such as open or closed doors, and several others. This gives a comprehensive picture rather than a single narrow test. The most striking finding is the scaling result. The researchers tested one of the more capable video generation systems at two different sizes: a smaller version and one with more than ten times as many parameters. More parameters didn't help. Scaling made the off-screen tracking problem measurably worse. The larger model produced more realistic-looking frames, but it was less accurate about what should have happened to the parts of the scene it wasn't

2026-07-02 原文 →
AI 资讯

Robot Police Officers

We’ve taken one small step towards robot police officers: a drone capable of disarming a suspect: In a June 22 video posted on the Sacramento County Sheriff’s Office’s Instagram page, an officer wearing goggles can be seen operating a drone to retrieve a knife from an armed suspect hiding inside a cluttered house. “After not responding to negotiators, a drone was deployed inside the residence,” the post says. “Drone pilots located the suspect hiding in a corner of a garage” and then used a high-powered magnet attached to the drone to grab the knife out of the suspect’s hand. In the video ­ which is soundtracked by the “Mission: Impossible” theme song—the intercepted knife can be seen spinning around in the air as the drone carries it back to the deputies...

2026-06-29 原文 →
AI 资讯

From Camera to Cloud: Netflix’s Scalable Media Processing Pipeline

Netflix has detailed a cloud-based system for scaling camera file processing across global film and TV workflows. The pipeline handles ingest, validation, metadata extraction, and media transformation at scale using FilmLight API and distributed compute. It standardizes workflows across editorial, VFX, and color pipelines, improving consistency and reducing manual handling across productions. By Leela Kumili

2026-06-18 原文 →
AI 资讯

Is Omni's conversational video editor as good as the demos?

Google's demo reel for Gemini Omni looks effortless: ask for a video, then keep talking to it until the shot is right. The question for developers is whether that conversational loop holds up outside a stage demo — and what it actually changes versus the Veo workflow it replaces. What Does Omni Add That Veo Couldn't? Omni's core addition is state. Veo produced one-shot renders — each prompt generated a fresh clip with no memory of the last. Gemini Omni holds context across turns, so changing the camera angle on turn three preserves the characters and lighting established on turn one without restarting the scene . Announced at Google I/O on May 19, 2026, the first shipped model, Gemini Omni Flash, replaces Veo as the video-generation surface in the Gemini app . Product director Nicole Brichtova framed it as "the next step towards combining the intelligence of Gemini with the rendering capabilities of our media models" — DeepMind's informal pitch is a "Nano Banana for video," extending conversational image editing to motion footage. Two claims deserve a skeptical read. Google advertises "intuitive understanding of forces like gravity, kinetic energy, and fluid dynamics," but those physics behaviors currently rest on Google demos and creator footage, with no third-party benchmarks published at launch . And on raw output, independent reviewers put Omni's generation quality on par with Veo 3.1 rather than clearly above it . The differentiation is the iterative editing loop and Gemini-grounded reasoning — not a new render engine. Before Starting: Paid Membership, Region, Age Omni access is gated behind a paid Google AI plan and a few hard eligibility rules, so confirm these before you open a prompt. Gemini Omni Flash unlocks in the Gemini app and Google Flow for Google AI Plus, Pro, and Ultra subscribers, with Plus starting at $7.99/month . If you want to test it for free, generation is available at no cost on YouTube Shorts and the YouTube Create App at launch . Two cons

2026-06-18 原文 →
AI 资讯

Why I built a native libmpv IPTV player for Windows — an HDR tone-mapping deep-dive

Up front, so there's no confusion: the app I'm describing (Nightmare TV) is a player only . You bring your own M3U / Xtream Codes playlist — it ships with no channels and no content. This post is about the playback engineering, not about where streams come from. Think "VLC for IPTV," not a content service. The problem that started it I watch a lot of live content on my PC — sports, mostly. And every IPTV player I tried on Windows fell into one of two buckets: An Android app running in an emulator. TiviMate and the good mobile players are Android-only, so on a desktop you end up in an emulator or a VM. Input lag, no real HDR path, fans spinning. A thin ExoPlayer / libVLC wrapper. These run natively, but most of them treat HDR as "pass the HDR10 metadata to the display and hope." On an SDR panel — or even a lot of HDR panels — bright skies in a football match blow out to a flat white blob, and 4K HEVC with a DTS track stutters because the decode path isn't doing what you think it is. I wanted the thing that didn't exist: a native Windows player with a reference-grade video path. So I built it on libmpv — the same playback core mpv uses — with a Flutter desktop shell on top for the UI. This post is the part I actually find interesting: the HDR tone-mapping pipeline. Why HDR "just passing through" isn't enough HDR10 content is mastered in the PQ (ST.2084) transfer function against a mastering display — often 1000 nits, sometimes 4000. Your screen is whatever it is: a 350-nit SDR laptop, a 600-nit "HDR400" monitor, an 800-nit OLED. If you map PQ straight to the panel, everything above the panel's peak just clips — all the highlight detail collapses to maximum white. Tone-mapping is the process of intelligently compressing the mastering range into the display range so you keep highlight detail instead of clipping it. The naive version (a fixed curve, or clipping) is what most wrapper players ship. The good version adapts to both the content and the display. The pipeline H

2026-06-06 原文 →
开发者

Defense tech is flooded with money, but who’s built to last?

Defense tech is red hot right now. Anduril and Mach Industries just doubled and quadrupled their valuations, respectively, and the U.S. government is proposing a 40% increase in defense budget. A wave of new startups is chasing those government contracts, but according to Ross Fubini, the venture investor who wrote Anduril’s first check, most of them will get lost in the Valley of Death between prototype contract […]

2026-06-04 原文 →
AI 资讯

Google just broke SEO. Here’s what replaces it.

Google I/O made it official: AI-generated answers are now front and center in search, and most brands have almost no visibility into how AI is describing them to their customers. For anyone who has spent years building a strategy around 10 blue links, the rules just changed in a pretty significant way. On this episode of TechCrunch’s Equity podcast, Rebecca […]

2026-05-27 原文 →