STRUCT V4L2_VP8_QUANTIZATION(9)

💅 NAME 💅

ok so bestie, welcome to the Kernel API Manual — this little page is all about struct v4l2_vp8_quantization, aka the VP8 quantization indices. that's it, that's the whole vibe. quant indices, in a struct, slaying 💖

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✨ SYNOPSIS ✨

like, here's the whole shape of it, no cap:

struct v4l2_vp8_quantization {
    __u8 y_ac_qi;
    __s8 y_dc_delta;
    __s8 y2_dc_delta;
    __s8 y2_ac_delta;
    __s8 uv_dc_delta;
    __s8 uv_ac_delta;
    __u16 padding;
 };

she's compact, she's iconic, she's seven fields of pure quantizer energy 🎀

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🫶 MEMBERS 🫶

okay let's meet the cast, one field at a time:

• y_ac_qi — luma AC coefficient table index. this is the index, the main character of the whole struct fr fr 👑
• y_dc_delta — the luma DC delta value. little signed number, big responsibilities ✨
• y2_dc_delta — the y2 block DC delta value. yes, y2 has her own DC delta, she's not sharing 🌸
• y2_ac_delta — and the y2 block AC delta value too. y2 stays booked and busy 💅
• uv_dc_delta — chroma DC delta value. chroma said "me too" 🦋
• uv_ac_delta — chroma AC delta value. the last of the delta girlies 😭
• padding — the padding field. and listen: it should be zeroed by applications. no thoughts, no data, just zeros. don't be weird about it 🙈

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🦋 DESCRIPTION 🦋

so, what is this thing even for? this struct holds the quantization indices that live in the 'quant_indices' part of the frame header syntax. yep — if you go look at the frame header, 'quant_indices' is right there, and these are her indices 💖

want the full lore? go read section '9.6. Dequantization Indices' of the VP8 specification. that's where the actual math and the actual details live — we're just holding the values here, not explaining the whole bitstream to you, iykyk 🧚

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🌈 SEE ALSO 🌈

okay this is the part where the manpage just. lists everything. and honestly? respect. go off bestie, here's the full guest list for the cookout:

• Kernel file ./include/uapi/linux/v4l2-controls.h
• enum v4l2_mpeg_video_av1_profile(9)
• enum v4l2_mpeg_video_av1_level(9)
• enum v4l2_stateless_h264_decode_mode(9)
• enum v4l2_stateless_h264_start_code(9)
• struct v4l2_ctrl_h264_sps(9)
• struct v4l2_ctrl_h264_pps(9)
• struct v4l2_ctrl_h264_scaling_matrix(9)
• struct v4l2_ctrl_h264_pred_weights(9)
• struct v4l2_h264_reference(9)
• struct v4l2_ctrl_h264_slice_params(9)
• struct v4l2_h264_dpb_entry(9)
• struct v4l2_ctrl_h264_decode_params(9)
• struct v4l2_ctrl_fwht_params(9)
• struct v4l2_vp8_segment(9)
• struct v4l2_vp8_loop_filter(9)
• struct v4l2_vp8_entropy(9)
• struct v4l2_vp8_entropy_coder_state(9)
• struct v4l2_ctrl_vp8_frame(9)
• struct v4l2_ctrl_mpeg2_sequence(9)
• struct v4l2_ctrl_mpeg2_picture(9)
• struct v4l2_ctrl_mpeg2_quantisation(9)
• struct v4l2_ctrl_hevc_sps(9)
• struct v4l2_ctrl_hevc_pps(9)
• struct v4l2_hevc_dpb_entry(9)
• struct v4l2_hevc_pred_weight_table(9)
• struct v4l2_ctrl_hevc_slice_params(9)
• struct v4l2_ctrl_hevc_decode_params(9)
• struct v4l2_ctrl_hevc_scaling_matrix(9)
• struct v4l2_vp9_loop_filter(9)
• struct v4l2_vp9_quantization(9)
• struct v4l2_vp9_segmentation(9)
• struct v4l2_ctrl_vp9_frame(9)
• struct v4l2_vp9_mv_probs(9)
• struct v4l2_ctrl_vp9_compressed_hdr(9)
• struct v4l2_ctrl_av1_sequence(9)
• struct v4l2_ctrl_av1_tile_group_entry(9)
• enum v4l2_av1_warp_model(9)
• enum v4l2_av1_reference_frame(9)
• struct v4l2_av1_global_motion(9)
• enum v4l2_av1_frame_restoration_type(9)
• struct v4l2_av1_loop_restoration(9)
• struct v4l2_av1_cdef(9)
• enum v4l2_av1_segment_feature(9)
• struct v4l2_av1_segmentation(9)
• struct v4l2_av1_loop_filter(9)
• struct v4l2_av1_quantization(9)
• struct v4l2_av1_tile_info(9)
• enum v4l2_av1_frame_type(9)
• enum v4l2_av1_interpolation_filter(9)
• enum v4l2_av1_tx_mode(9)
• struct v4l2_ctrl_av1_frame(9)
• struct v4l2_ctrl_av1_film_grain(9)

literally every codec showed up to this one SEE ALSO. h264, vp8, vp9, av1, mpeg2, hevc, fwht — the whole group chat is here 🫶

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okay that's the page!! this one's a wrap 🎀 signed off from ./include/uapi/linux, dated October 2026, and filed under struct v4l2_...quantization(9) — go quantize something cute, bestie 💜✨