FFmpeg
Data Structures | Macros | Typedefs | Enumerations | Functions | Variables
vf_palettegen.c File Reference
#include "libavutil/avassert.h"
#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "libavutil/qsort.h"
#include "libavutil/intreadwrite.h"
#include "avfilter.h"
#include "internal.h"

Go to the source code of this file.

Data Structures

struct  color_ref
 
struct  range_box
 
struct  hist_node
 
struct  PaletteGenContext
 

Macros

#define NBITS   5
 
#define HIST_SIZE   (1<<(4*NBITS))
 
#define OFFSET(x)   offsetof(PaletteGenContext, x)
 
#define FLAGS   AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
#define DECLARE_CMP_FUNC(name, pos)
 

Typedefs

typedef int(* cmp_func) (const void *, const void *)
 

Enumerations

enum  { STATS_MODE_ALL_FRAMES, STATS_MODE_DIFF_FRAMES, STATS_MODE_SINGLE_FRAMES, NB_STATS_MODE }
 

Functions

 AVFILTER_DEFINE_CLASS (palettegen)
 
static int query_formats (AVFilterContext *ctx)
 
static int cmp_color (const void *a, const void *b)
 Simple color comparison for sorting the final palette. More...
 
static av_always_inline int diff (const uint32_t a, const uint32_t b)
 
static av_always_inline int diff_alpha (const uint32_t a, const uint32_t b)
 
static int get_next_box_id_to_split (PaletteGenContext *s)
 Find the next box to split: pick the one with the highest variance. More...
 
static uint32_t get_avg_color (struct color_ref *const *refs, const struct range_box *box, int use_alpha)
 Get the 32-bit average color for the range of RGB colors enclosed in the specified box. More...
 
static void split_box (PaletteGenContext *s, struct range_box *box, int n)
 Split given box in two at position n. More...
 
static void write_palette (AVFilterContext *ctx, AVFrame *out)
 Write the palette into the output frame. More...
 
static struct color_ref ** load_color_refs (const struct hist_node *hist, int nb_refs)
 Crawl the histogram to get all the defined colors, and create a linear list of them (each color reference entry is a pointer to the value in the histogram/hash table). More...
 
static double set_colorquant_ratio_meta (AVFrame *out, int nb_out, int nb_in)
 
static AVFrameget_palette_frame (AVFilterContext *ctx)
 Main function implementing the Median Cut Algorithm defined by Paul Heckbert in Color Image Quantization for Frame Buffer Display (1982) More...
 
static unsigned color_hash (uint32_t color, int use_alpha)
 Hashing function for the color. More...
 
static int color_inc (struct hist_node *hist, uint32_t color, int use_alpha)
 Locate the color in the hash table and increment its counter. More...
 
static int update_histogram_diff (struct hist_node *hist, const AVFrame *f1, const AVFrame *f2, int use_alpha)
 Update histogram when pixels differ from previous frame. More...
 
static int update_histogram_frame (struct hist_node *hist, const AVFrame *f, int use_alpha)
 Simple histogram of the frame. More...
 
static int filter_frame (AVFilterLink *inlink, AVFrame *in)
 Update the histogram for each passing frame. More...
 
static int request_frame (AVFilterLink *outlink)
 Returns only one frame at the end containing the full palette. More...
 
static int config_output (AVFilterLink *outlink)
 The output is one simple 16x16 squared-pixels palette. More...
 
static int init (AVFilterContext *ctx)
 
static av_cold void uninit (AVFilterContext *ctx)
 

Variables

static const AVOption palettegen_options []
 
static const cmp_func cmp_funcs [] = {cmp_a, cmp_r, cmp_g, cmp_b}
 
static const AVFilterPad palettegen_inputs []
 
static const AVFilterPad palettegen_outputs []
 
const AVFilter ff_vf_palettegen
 

Detailed Description

Generate one palette for a whole video stream.

Definition in file vf_palettegen.c.

Macro Definition Documentation

◆ NBITS

#define NBITS   5

Definition at line 61 of file vf_palettegen.c.

◆ HIST_SIZE

#define HIST_SIZE   (1<<(4*NBITS))

Definition at line 62 of file vf_palettegen.c.

◆ OFFSET

#define OFFSET (   x)    offsetof(PaletteGenContext, x)

Definition at line 82 of file vf_palettegen.c.

◆ FLAGS

Definition at line 83 of file vf_palettegen.c.

◆ DECLARE_CMP_FUNC

#define DECLARE_CMP_FUNC (   name,
  pos 
)
Value:
static int cmp_##name(const void *pa, const void *pb) \
{ \
const struct color_ref * const *a = pa; \
const struct color_ref * const *b = pb; \
return (int)((*a)->color >> (8 * (3 - (pos))) & 0xff) \
- (int)((*b)->color >> (8 * (3 - (pos))) & 0xff); \
}

Definition at line 113 of file vf_palettegen.c.

Typedef Documentation

◆ cmp_func

typedef int(* cmp_func) (const void *, const void *)

Definition at line 111 of file vf_palettegen.c.

Enumeration Type Documentation

◆ anonymous enum

anonymous enum
Enumerator
STATS_MODE_ALL_FRAMES 
STATS_MODE_DIFF_FRAMES 
STATS_MODE_SINGLE_FRAMES 
NB_STATS_MODE 

Definition at line 54 of file vf_palettegen.c.

Function Documentation

◆ AVFILTER_DEFINE_CLASS()

AVFILTER_DEFINE_CLASS ( palettegen  )

◆ query_formats()

static int query_formats ( AVFilterContext ctx)
static

Definition at line 98 of file vf_palettegen.c.

◆ cmp_color()

static int cmp_color ( const void *  a,
const void *  b 
)
static

Simple color comparison for sorting the final palette.

Definition at line 132 of file vf_palettegen.c.

Referenced by get_palette_frame().

◆ diff()

static av_always_inline int diff ( const uint32_t  a,
const uint32_t  b 
)
static

Definition at line 139 of file vf_palettegen.c.

Referenced by activate(), add_hfyu_median_pred_int16_c(), add_lag_median_prediction(), add_median_pred_c(), add_median_prediction(), adpcm_ct_expand_nibble(), adpcm_decode_frame(), adpcm_ima_alp_compress_sample(), adpcm_ima_alp_expand_nibble(), adpcm_ima_expand_nibble(), adpcm_ima_oki_expand_nibble(), adpcm_ima_qt_compress_sample(), adpcm_ima_qt_expand_nibble(), adpcm_ima_wav_expand_nibble(), adpcm_sbpro_expand_nibble(), amplify_frame(), aptx_encode_channel(), arith2_get_consumed_bytes(), asf_read_frame_header(), block_angle(), blur(), build_diff_map(), calc_slice_sizes(), cbs_av1_get_relative_dist(), celt_decode_tf_changes(), celt_enc_tf(), celt_quant_fine(), check_add_median_pred(), codebook_sanity_check_for_rate_quarter(), comp_harmonic_coeff(), compare_blocks(), compute_target_delay(), config_filter(), copy_region_enc(), deband_16_c(), deband_8_c(), decode_channel_sf_idx(), decode_channel_wordlen(), decode_dc(), decode_frame(), decode_line_TMPL(), decode_residual(), decode_tones_amplitude(), dering_TMPL(), detect_scene_change(), diff_c(), dnxhd_calc_bits_thread(), dnxhd_encode_dc(), do_chromahold16_slice(), do_chromahold_slice(), do_chromakey_pixel(), do_chromakey_pixel16(), do_colorkey_pixel(), do_hsvkey_pixel(), dpcm_decode_frame(), dpcm_predict(), draw_spatial(), dts_probe(), encode_block(), encode_dc(), encode_high(), encode_line_TMPL(), encode_low(), encode_residual_ch(), encode_scale_factors(), enqueue_packet(), est_alpha_diff(), estimate_pitch(), eval_sse(), exp_quant_coarse(), fbdev_write_packet(), ff_dcaadpcm_subband_analysis(), ff_libwebp_get_frame(), ff_mpeg1_decode_block_intra(), ff_mpeg4_encode_mb(), ff_rate_estimate_qscale(), filter_frame(), find_block_motion(), find_missing_packets(), find_timestamp_in_playlist(), fixed_gain_smooth(), fold(), get_closest_codebook(), get_next_box_id_to_split(), get_pts(), get_relative_dist(), get_scene_score(), get_video_frame(), glyph_cmp(), h263_decode_block(), index_mb(), init_quantized_coeffs_elem0(), inv_predict_11(), IsAlmostEqual(), limitdiff16(), limitdiff8(), ljpeg_encode_bgr(), lsf2lsp(), lsf_decode(), magicyuv_median_pred16(), main(), make_noises(), max_component_diff(), mdec_decode_block_intra(), mf_enca_output_score(), motion_search(), movie_push_frame(), mpeg2_decode_block_intra(), mpeg2_fast_decode_block_intra(), mvi_predict(), no_codebook_bits(), parse_playlist(), parse_tonal(), perform_dc_correction(), pixel_color7_slow(), process_subpacket_9(), put_alpha_diff(), pxr24_uncompress(), rgb2yuv_fsb(), rtp_parse_one_packet(), rv30_weak_loop_filter(), rv40_weak_loop_filter(), sad_hv_bilinear_filter_16width_msa(), sad_hv_bilinear_filter_8width_msa(), select_from_pts_buffer(), silk_stabilize_lsf(), speedhq_init_static_data(), svq1_decode_motion_vector(), swap_samplerates_on_filter(), synchronize_audio(), tm2_null_res_block(), truemotion2rt_decode_frame(), update_qscale(), validate_options(), vp8_handle_packet(), wavpack_encode_block(), and wmv2_pred_motion().

◆ diff_alpha()

static av_always_inline int diff_alpha ( const uint32_t  a,
const uint32_t  b 
)
static

Definition at line 149 of file vf_palettegen.c.

Referenced by get_next_box_id_to_split().

◆ get_next_box_id_to_split()

static int get_next_box_id_to_split ( PaletteGenContext s)
static

Find the next box to split: pick the one with the highest variance.

Definition at line 163 of file vf_palettegen.c.

Referenced by get_palette_frame().

◆ get_avg_color()

static uint32_t get_avg_color ( struct color_ref *const *  refs,
const struct range_box box,
int  use_alpha 
)
static

Get the 32-bit average color for the range of RGB colors enclosed in the specified box.

Takes into account the weight of each color.

Definition at line 203 of file vf_palettegen.c.

Referenced by get_palette_frame(), and split_box().

◆ split_box()

static void split_box ( PaletteGenContext s,
struct range_box box,
int  n 
)
static

Split given box in two at position n.

The original box becomes the left part of the split, and the new index box is the right part.

Definition at line 236 of file vf_palettegen.c.

Referenced by get_palette_frame().

◆ write_palette()

static void write_palette ( AVFilterContext ctx,
AVFrame out 
)
static

Write the palette into the output frame.

Definition at line 256 of file vf_palettegen.c.

Referenced by get_palette_frame().

◆ load_color_refs()

static struct color_ref** load_color_refs ( const struct hist_node hist,
int  nb_refs 
)
static

Crawl the histogram to get all the defined colors, and create a linear list of them (each color reference entry is a pointer to the value in the histogram/hash table).

Definition at line 289 of file vf_palettegen.c.

Referenced by get_palette_frame().

◆ set_colorquant_ratio_meta()

static double set_colorquant_ratio_meta ( AVFrame out,
int  nb_out,
int  nb_in 
)
static

Definition at line 307 of file vf_palettegen.c.

Referenced by get_palette_frame().

◆ get_palette_frame()

static AVFrame* get_palette_frame ( AVFilterContext ctx)
static

Main function implementing the Median Cut Algorithm defined by Paul Heckbert in Color Image Quantization for Frame Buffer Display (1982)

Definition at line 320 of file vf_palettegen.c.

Referenced by filter_frame(), and request_frame().

◆ color_hash()

static unsigned color_hash ( uint32_t  color,
int  use_alpha 
)
inlinestatic

Hashing function for the color.

It keeps the NBITS least significant bit of each component to make it "random" even if the scene doesn't have much different colors.

Definition at line 430 of file vf_palettegen.c.

Referenced by color_inc().

◆ color_inc()

static int color_inc ( struct hist_node hist,
uint32_t  color,
int  use_alpha 
)
static

Locate the color in the hash table and increment its counter.

Definition at line 447 of file vf_palettegen.c.

Referenced by update_histogram_diff(), and update_histogram_frame().

◆ update_histogram_diff()

static int update_histogram_diff ( struct hist_node hist,
const AVFrame f1,
const AVFrame f2,
int  use_alpha 
)
static

Update histogram when pixels differ from previous frame.

Definition at line 474 of file vf_palettegen.c.

Referenced by filter_frame().

◆ update_histogram_frame()

static int update_histogram_frame ( struct hist_node hist,
const AVFrame f,
int  use_alpha 
)
static

Simple histogram of the frame.

Definition at line 498 of file vf_palettegen.c.

Referenced by filter_frame().

◆ filter_frame()

static int filter_frame ( AVFilterLink inlink,
AVFrame in 
)
static

Update the histogram for each passing frame.

No frame will be pushed here.

Definition at line 518 of file vf_palettegen.c.

◆ request_frame()

static int request_frame ( AVFilterLink outlink)
static

Returns only one frame at the end containing the full palette.

Definition at line 556 of file vf_palettegen.c.

◆ config_output()

static int config_output ( AVFilterLink outlink)
static

The output is one simple 16x16 squared-pixels palette.

Definition at line 575 of file vf_palettegen.c.

◆ init()

static int init ( AVFilterContext ctx)
static

Definition at line 582 of file vf_palettegen.c.

◆ uninit()

static av_cold void uninit ( AVFilterContext ctx)
static

Definition at line 592 of file vf_palettegen.c.

Variable Documentation

◆ palettegen_options

const AVOption palettegen_options[]
static
Initial value:
= {
{ "max_colors", "set the maximum number of colors to use in the palette", OFFSET(max_colors), AV_OPT_TYPE_INT, {.i64=256}, 4, 256, FLAGS },
{ "reserve_transparent", "reserve a palette entry for transparency", OFFSET(reserve_transparent), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
{ "transparency_color", "set a background color for transparency", OFFSET(transparency_color), AV_OPT_TYPE_COLOR, {.str="lime"}, 0, 0, FLAGS },
{ "stats_mode", "set statistics mode", OFFSET(stats_mode), AV_OPT_TYPE_INT, {.i64=STATS_MODE_ALL_FRAMES}, 0, NB_STATS_MODE-1, FLAGS, "mode" },
{ "full", "compute full frame histograms", 0, AV_OPT_TYPE_CONST, {.i64=STATS_MODE_ALL_FRAMES}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "diff", "compute histograms only for the part that differs from previous frame", 0, AV_OPT_TYPE_CONST, {.i64=STATS_MODE_DIFF_FRAMES}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "single", "compute new histogram for each frame", 0, AV_OPT_TYPE_CONST, {.i64=STATS_MODE_SINGLE_FRAMES}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "use_alpha", "create a palette including alpha values", OFFSET(use_alpha), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS },
{ NULL }
}

Definition at line 84 of file vf_palettegen.c.

◆ cmp_funcs

const cmp_func cmp_funcs[] = {cmp_a, cmp_r, cmp_g, cmp_b}
static

Definition at line 127 of file vf_palettegen.c.

Referenced by get_palette_frame().

◆ palettegen_inputs

const AVFilterPad palettegen_inputs[]
static
Initial value:
= {
{
.name = "default",
.filter_frame = filter_frame,
},
}

Definition at line 603 of file vf_palettegen.c.

◆ palettegen_outputs

const AVFilterPad palettegen_outputs[]
static
Initial value:
= {
{
.name = "default",
.config_props = config_output,
.request_frame = request_frame,
},
}

Definition at line 611 of file vf_palettegen.c.

◆ ff_vf_palettegen

const AVFilter ff_vf_palettegen
Initial value:
= {
.name = "palettegen",
.description = NULL_IF_CONFIG_SMALL("Find the optimal palette for a given stream."),
.priv_size = sizeof(PaletteGenContext),
.init = init,
.priv_class = &palettegen_class,
}

Definition at line 620 of file vf_palettegen.c.

request_frame
static int request_frame(AVFilterLink *outlink)
Returns only one frame at the end containing the full palette.
Definition: vf_palettegen.c:556
name
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option name
Definition: writing_filters.txt:88
config_output
static int config_output(AVFilterLink *outlink)
The output is one simple 16x16 squared-pixels palette.
Definition: vf_palettegen.c:575
b
#define b
Definition: input.c:40
FILTER_QUERY_FUNC
#define FILTER_QUERY_FUNC(func)
Definition: internal.h:168
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Update the histogram for each passing frame.
Definition: vf_palettegen.c:518
init
static int init(AVFilterContext *ctx)
Definition: vf_palettegen.c:582
FLAGS
#define FLAGS
Definition: vf_palettegen.c:83
OFFSET
#define OFFSET(x)
Definition: vf_palettegen.c:82
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_palettegen.c:592
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:191
NULL
#define NULL
Definition: coverity.c:32
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: vf_palettegen.c:98
AV_OPT_TYPE_COLOR
@ AV_OPT_TYPE_COLOR
Definition: opt.h:239
STATS_MODE_ALL_FRAMES
@ STATS_MODE_ALL_FRAMES
Definition: vf_palettegen.c:55
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
NB_STATS_MODE
@ NB_STATS_MODE
Definition: vf_palettegen.c:58
PaletteGenContext
Definition: vf_palettegen.c:64
STATS_MODE_DIFF_FRAMES
@ STATS_MODE_DIFF_FRAMES
Definition: vf_palettegen.c:56
palettegen_outputs
static const AVFilterPad palettegen_outputs[]
Definition: vf_palettegen.c:611
pos
unsigned int pos
Definition: spdifenc.c:412
color_ref
Definition: vf_palettegen.c:35
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
palettegen_inputs
static const AVFilterPad palettegen_inputs[]
Definition: vf_palettegen.c:603
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
STATS_MODE_SINGLE_FRAMES
@ STATS_MODE_SINGLE_FRAMES
Definition: vf_palettegen.c:57
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:241
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:192
int
int
Definition: ffmpeg_filter.c:156
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:233