nal_h264_write_pps(9)

📦 version 7.3.1, in nixpkgs unstable

✨ nal_h264_write_pps — the PPS glow-up page ✨

ok bestie, so this one lives in the Kernel API Manual, section 9, and it's literally the function that takes your PPS and makes it RBSP. no cap, that's the whole vibe. 🎀

💖 NAME 💖

nal_h264_write_pps — write a PPS NAL unit into RBSP format. that's it, that's the function, and she ate. ✨

🌸 SYNOPSIS 🌸

ssize_t nal_h264_write_pps (const struct device *dev , void *dest ,
size_t n , struct nal_h264_pps *pps );

look at her. four arguments, one ssize_t return, main character energy all the way through. 💅

🦋 ARGUMENTS 🦋

  • dev — the device pointer. yeah, she's just there being a device pointer, iconic of her.
  • dest — the buffer that gets filled with RBSP data. this is where the magic lands, bestie. 🫶
  • n — the maximum size of dest, in bytes. like, the hard limit, do not test her.
  • pps — the struct nal_h264_pps you want converted to RBSP. this is the actual payload of the whole situation.

👑 DESCRIPTION 👑

so here's the tea: this function converts pps to RBSP data and writes it into dest. lowkey simple, highkey important. ✨

but!! and this is the part you actually need to know — the size of the PPS NAL unit is not known in advance. not even a little. so if dest doesn't hold sufficient space for the PPS NAL unit, this function will fail. 😭

💀 warning vibe check: there is no "oops let me grow the buffer for you" here. the space has to be there already, or she's not writing anything. size it generous, bestie.

🌈 RETURN 🌈

  • the number of bytes written to dest 🔥
  • or a negative error code 😭

that's the whole deal. positive-ish count = slay, negative = nope.

🍓 SEE ALSO 🍓

the kernel file, for the curious:

  • ./drivers/media/platform/allegro-dvt/nal-h264.c

and the rest of the NAL friend group, all iconic, all worth a read:

like genuinely, read the whole set, they're giving squad goals. 💜

ok that's the page, mwah 💋

and for the cute sign-off: this beauty comes from ./drivers/media/platform/alleg..., dated October 2026, and she answers to the name nal_h264_write_pps(9) — that's her whole government name, periodt. 🎀✨

📦 where this page comes from