Go to the documentation of this file.
   91 #define OFFSET(x) offsetof(CurvesContext, x) 
   92 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM 
  125 static const struct {
 
  132         "0.129/1 0.466/0.498 0.725/0",
 
  133         "0.109/1 0.301/0.498 0.517/0",
 
  134         "0.098/1 0.235/0.498 0.423/0",
 
  137         "0/0 0.25/0.156 0.501/0.501 0.686/0.745 1/1",
 
  138         "0/0 0.25/0.188 0.38/0.501 0.745/0.815 1/0.815",
 
  139         "0/0 0.231/0.094 0.709/0.874 1/1",
 
  149         "0/0.11 0.42/0.51 1/0.95",
 
  151         "0/0.22 0.49/0.44 1/0.8",
 
  172     const int scale = lut_size - 1;
 
  179         point->
x = 
av_strtod(p, &p); 
if (p && *p) p++;
 
  180         point->
y = 
av_strtod(p, &p); 
if (p && *p) p++;
 
  181         if (point->
x < 0 || point->
x > 1 || point->
y < 0 || point->
y > 1) {
 
  183                    "x and y must be in the [0;1] range.\n", point->
x, point->
y);
 
  189             if ((
int)(last->
x * 
scale) >= (
int)(point->
x * 
scale)) {
 
  191                        "and (%f;%f) are too close from each other or not " 
  192                        "strictly increasing on the x-axis\n",
 
  193                        last->
x, last->
y, point->
x, point->
y);
 
  201     if (*points && !(*points)->
next) {
 
  203                "this is unlikely to behave as you expect. You probably want" 
  204                "at least 2 points.",
 
  205                (*points)->x, (*points)->y);
 
  227 #define CLIP(v) (nbits == 8 ? av_clip_uint8(v) : av_clip_uintp2_c(v, nbits)) 
  230                               const struct keypoint *points, 
int nbits)
 
  233     const struct keypoint *point = points;
 
  235     const int lut_size = 1<<nbits;
 
  236     const int scale = lut_size - 1;
 
  243         for (
i = 0; 
i < lut_size; 
i++)
 
  249         for (
i = 0; 
i < lut_size; 
i++)
 
  265     for (point = points; point; point = point->
next) {
 
  267             h[
i] = point->
x - xprev;
 
  274     for (
i = 1; 
i < n - 1; 
i++) {
 
  275         const double yp = point->
y;
 
  276         const double yc = point->
next->
y;
 
  278         r[
i] = 6 * ((yn-yc)/
h[
i] - (yc-yp)/
h[
i-1]);
 
  288     for (
i = 1; 
i < n - 1; 
i++) {
 
  295     for (
i = 1; 
i < n; 
i++) {
 
  297         const double k = den ? 1./den : 1.;
 
  301     for (
i = n - 2; 
i >= 0; 
i--)
 
  313     while (point->
next) {
 
  314         const double yc = point->
y;
 
  315         const double yn = point->
next->
y;
 
  318         const double b = (yn-yc)/
h[
i] - 
h[
i]*
r[
i]/2. - 
h[
i]*(
r[
i+1]-
r[
i])/6.;
 
  319         const double c = 
r[
i] / 2.;
 
  320         const double d = (
r[
i+1] - 
r[
i]) / (6.*
h[
i]);
 
  323         const int x_start = point->
x       * 
scale;
 
  326         av_assert0(x_start >= 0 && x_start < lut_size &&
 
  327                    x_end   >= 0 && x_end   < lut_size);
 
  329         for (
x = x_start; 
x <= x_end; 
x++) {
 
  330             const double xx = (
x - x_start) * 1./
scale;
 
  331             const double yy = 
a + 
b*xx + 
c*xx*xx + 
d*xx*xx*xx;
 
  341     for (
i = (
int)(point->
x * 
scale); 
i < lut_size; 
i++)
 
  352 #define SIGN(x) (x > 0.0 ? 1 : x < 0.0 ? -1 : 0) 
  373     d = ((2 * 
h0 + h1) * m0 - 
h0 * m1) / (
h0 + h1);
 
  379     else if (mask2) 
d = 3.0 * m0;
 
  410     for (
int i = 0; 
i < n; 
i++) smk[
i] = 
SIGN(mk[
i]);
 
  413     for (
int i = 0; 
i < m; 
i++) {
 
  414         int8_t condition = (smk[
i + 1] != smk[
i]) || (mk[
i + 1] == 0) || (mk[
i] == 0);
 
  418             double w1 = 2 * hk[
i + 1] + hk[
i];
 
  419             double w2 = hk[
i + 1] + 2 * hk[
i];
 
  420             dk[
i + 1] = (w1 + w2) / (w1 / mk[
i] + w2 / mk[
i + 1]);
 
  444     double x2 = 
x * 
x, x3 = x2 * 
x;
 
  445     return f * (3.0 * x2 - 2.0 * x3) + 
d * (x3 - x2);
 
  463                                     const struct keypoint *points, 
int nbits)
 
  465     const struct keypoint *point = points;
 
  466     const int lut_size = 1<<nbits;
 
  468     double *
xi, *fi, *di, *hi, *
mi;
 
  469     const int scale = lut_size - 1; 
 
  476         for (
int i = 0; 
i < lut_size; 
i++) 
y[
i] = 
i;
 
  483         for (
int i = 0; 
i < lut_size; 
i++) 
y[
i] = yval;
 
  499     for (
int i = 0; 
i < n; 
i++) {
 
  506     for (
int i = 0; 
i < n - 1; 
i++) {
 
  514         const double m = 
mi[0], 
b = fi[0] - 
xi[0]*m;
 
  515         for (
int i = 0; 
i < lut_size; 
i++) 
y[
i] = 
CLIP(
i*m + 
b);
 
  528         const double xi0 = 
xi[0];
 
  529         const double yi0 = fi[0];
 
  530         const uint16_t yval = 
CLIP(yi0);
 
  531         for (; 
x < xi0; 
x++) {
 
  539     for (
int i = 0, x0 = 
x; 
i < n-1; 
i++, x0 = 
x) {
 
  540         const double xi0 = 
xi[
i];     
 
  541         const double xi1 = 
xi[
i + 1]; 
 
  542         const double h = hi[
i];       
 
  543         const double f0 = fi[
i];      
 
  544         const double f1 = fi[
i + 1];  
 
  545         const double d0 = di[
i];      
 
  546         const double d1 = di[
i + 1];  
 
  549         for (; 
x < xi1; 
x++) { 
 
  550             const double xx = (
x - xi0) / 
h; 
 
  559                                                     i, x0, 
x-1, 
y[x0], 
y[
x-1]);
 
  564     if (
x && 
x < lut_size) {
 
  566         const double xi1 = 
xi[n - 1];
 
  567         const double yi1 = fi[n - 1];
 
  568         const uint16_t yval = 
CLIP(yi1);
 
  570                                                 n-1, 
x, lut_size - 1, yval);
 
  571         for (; 
x && 
x < lut_size; 
x++) { 
 
  590     static const int comp_ids[] = {3, 0, 1, 2};
 
  598 #define READ16(dst) do {                \ 
  600         ret = AVERROR_INVALIDDATA;      \ 
  603     dst = AV_RB16(buf);                 \ 
  614         for (n = 0; n < nb_points; n++) {
 
  621             char **
pts = &
curves->comp_points_str[comp_ids[
i]];
 
  625                        i, comp_ids[
i], nb_points, *
pts);
 
  645     const double scale = 1. / (lut_size - 1);
 
  646     static const char * 
const colors[] = { 
"red", 
"green", 
"blue", 
"#404040", };
 
  666         av_bprintf(&buf, 
"%s'-' using 1:2 with lines lc '%s' title ''",
 
  667                    i ? 
", " : 
"plot ", colors[
i]);
 
  669             av_bprintf(&buf, 
", '-' using 1:2 with points pointtype 3 lc '%s' title ''",
 
  678         for (
x = 0; 
x < lut_size; 
x++)
 
  683         if (comp_points[
i]) {
 
  684             const struct keypoint *point = comp_points[
i];
 
  694     fwrite(buf.str, 1, buf.len, 
f);
 
  705     const char *allp = 
curves->comp_points_str_all;
 
  723         curves->parsed_psfile = 1;
 
  727 #define SET_COMP_IF_NOT_SET(n, name) do {                           \ 
  728     if (!pts[n] && curves_presets[curves->preset].name) {           \ 
  729         pts[n] = av_strdup(curves_presets[curves->preset].name);    \ 
  731             return AVERROR(ENOMEM);                                 \ 
  751     const int direct = 
out == in;
 
  753     const uint8_t 
r = 
curves->rgba_map[
R];
 
  754     const uint8_t 
g = 
curves->rgba_map[
G];
 
  755     const uint8_t 
b = 
curves->rgba_map[
B];
 
  756     const uint8_t 
a = 
curves->rgba_map[
A];
 
  762             uint16_t       *dstp = (      uint16_t *)(
out->data[0] + 
y * 
out->linesize[0]);
 
  763             const uint16_t *srcp = (
const uint16_t *)(in ->
data[0] + 
y *  in->
linesize[0]);
 
  769                 if (!direct && 
step == 4)
 
  770                     dstp[
x + 
a] = srcp[
x + 
a];
 
  782                 if (!direct && 
step == 4)
 
  785             dst += 
out->linesize[0];
 
  799     const int direct = 
out == in;
 
  801     const uint8_t 
r = 
curves->rgba_map[
R];
 
  802     const uint8_t 
g = 
curves->rgba_map[
G];
 
  803     const uint8_t 
b = 
curves->rgba_map[
B];
 
  804     const uint8_t 
a = 
curves->rgba_map[
A];
 
  810             uint16_t       *dstrp = (      uint16_t *)(
out->data[
r] + 
y * 
out->linesize[
r]);
 
  811             uint16_t       *dstgp = (      uint16_t *)(
out->data[
g] + 
y * 
out->linesize[
g]);
 
  812             uint16_t       *dstbp = (      uint16_t *)(
out->data[
b] + 
y * 
out->linesize[
b]);
 
  813             uint16_t       *dstap = (      uint16_t *)(
out->data[
a] + 
y * 
out->linesize[
a]);
 
  814             const uint16_t *srcrp = (
const uint16_t *)(in ->
data[
r] + 
y *  in->
linesize[
r]);
 
  815             const uint16_t *srcgp = (
const uint16_t *)(in ->
data[
g] + 
y *  in->
linesize[
g]);
 
  816             const uint16_t *srcbp = (
const uint16_t *)(in ->
data[
b] + 
y *  in->
linesize[
b]);
 
  817             const uint16_t *srcap = (
const uint16_t *)(in ->
data[
a] + 
y *  in->
linesize[
a]);
 
  823                 if (!direct && 
step == 4)
 
  842                 if (!direct && 
step == 4)
 
  845             dstr += 
out->linesize[
r];
 
  846             dstg += 
out->linesize[
g];
 
  847             dstb += 
out->linesize[
b];
 
  848             dsta += 
out->linesize[
a];
 
  892             for (j = 0; j < 
curves->lut_size; j++)
 
  898             const struct keypoint *point = comp_points[
i];
 
  955                            char *res, 
int res_len, 
int flags)
 
  960     if (!strcmp(cmd, 
"plot")) {
 
  962     } 
else if (!strcmp(cmd, 
"all") || !strcmp(cmd, 
"preset") || !strcmp(cmd, 
"psfile")  || !strcmp(cmd, 
"interp")) {
 
  963         if (!strcmp(cmd, 
"psfile"))
 
  964             curves->parsed_psfile = 0;
 
  970     } 
else if (!strcmp(cmd, 
"red") || !strcmp(cmd, 
"r")) {
 
  972     } 
else if (!strcmp(cmd, 
"green") || !strcmp(cmd, 
"g")) {
 
  974     } 
else if (!strcmp(cmd, 
"blue") || !strcmp(cmd, 
"b")) {
 
  976     } 
else if (!strcmp(cmd, 
"master") || !strcmp(cmd, 
"m")) {
 
 1029     .priv_class    = &curves_class,
 
  
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
#define AV_PIX_FMT_GBRAP16
#define AV_LOG_WARNING
Something somehow does not look correct.
#define AV_BPRINT_SIZE_UNLIMITED
static const float h0[64]
uint16_t * graph[NB_COMP+1]
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
static int dump_curves(const char *fname, uint16_t *graph[NB_COMP+1], struct keypoint *comp_points[NB_COMP+1], int lut_size)
static double interp_cubic_hermite_half(const double x, const double f, const double d)
Evalaute half of the cubic hermite interpolation expression, wrt one interval endpoint.
static const Curve curves[]
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
This structure describes decoded (raw) audio or video data.
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about which is also called distortion Distortion can be quantified by almost any quality measurement one chooses the sum of squared differences is used but more complex methods that consider psychovisual effects can be used as well It makes no difference in this discussion First step
static const AVFilterPad curves_inputs[]
#define AV_LOG_VERBOSE
Detailed information.
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
@ AV_PIX_FMT_BGRA
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
const char * name
Filter name.
static int get_nb_points(const struct keypoint *d)
A link between two filters.
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
int(* filter_slice)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
#define AV_PIX_FMT_GBRP14
int av_file_map(const char *filename, uint8_t **bufptr, size_t *size, int log_offset, void *log_ctx)
Read the file with name filename, and put its content in a newly allocated buffer or map it with mmap...
@ AV_PIX_FMT_GBRAP
planar GBRA 4:4:4:4 32bpp
#define AV_PIX_FMT_GBRP10
#define AV_BPRINT_SIZE_AUTOMATIC
static double val(void *priv, double ch)
A filter pad used for either input or output.
static int slice_start(SliceContext *sc, VVCContext *s, VVCFrameContext *fc, const CodedBitstreamUnit *unit, const int is_first_slice)
#define AV_LOG_TRACE
Extremely verbose debugging, useful for libav* development.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
#define FF_ARRAY_ELEMS(a)
const AVFilterPad ff_video_default_filterpad[1]
An AVFilterPad array whose only entry has name "default" and is of type AVMEDIA_TYPE_VIDEO.
static const uint16_t mask[17]
#define AV_PIX_FMT_GBRAP10
#define AV_PIX_FMT_GBRAP12
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
static int slice_end(AVCodecContext *avctx, AVFrame *pict)
Handle slice ends.
#define av_assert0(cond)
assert() equivalent, that is always enabled.
#define CLIP(v)
Natural cubic spline interpolation Finding curves using Cubic Splines notes by Steven Rauch and John ...
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
AVFILTER_DEFINE_CLASS(curves)
#define xi(width, name, var, range_min, range_max, subs,...)
#define FILTER_INPUTS(array)
void av_file_unmap(uint8_t *bufptr, size_t size)
Unmap or free the buffer bufptr created by av_file_map().
@ AV_PIX_FMT_RGBA
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
int av_log_get_level(void)
Get the current log level.
#define AV_PIX_FMT_GBRP16
#define AV_PIX_FMT_RGBA64
Describe the class of an AVClass context structure.
static int interpolate(void *log_ctx, uint16_t *y, const struct keypoint *points, int nbits)
static __device__ float fabs(float a)
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
@ AV_PIX_FMT_BGR0
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
@ AV_PIX_FMT_ABGR
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
int(* init)(AVBSFContext *ctx)
@ AV_PIX_FMT_RGB24
packed RGB 8:8:8, 24bpp, RGBRGB...
static void scale(int *out, const int *in, const int w, const int h, const int shift)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
int av_get_padded_bits_per_pixel(const AVPixFmtDescriptor *pixdesc)
Return the number of bits per pixel for the pixel format described by pixdesc, including any padding ...
#define FILTER_PIXFMTS(...)
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
const AVFilter ff_vf_curves
static av_cold void curves_uninit(AVFilterContext *ctx)
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
static int filter_slice_planar(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Generic processing of user supplied commands that are set in the same way as the filter options.
static const AVOption curves_options[]
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
@ AV_PIX_FMT_RGB0
packed RGB 8:8:8, 32bpp, RGBXRGBX... X=unused/undefined
static int filter_slice_packed(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
@ AV_PIX_FMT_ARGB
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
char * comp_points_str[NB_COMP+1]
@ PRESET_INCREASE_CONTRAST
static void uninit(AVBSFContext *ctx)
#define AV_PIX_FMT_BGRA64
#define i(width, name, range_min, range_max)
int w
agreed upon image width
#define AV_PIX_FMT_GBRP12
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Used for passing data between threads.
static const struct @267 curves_presets[]
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
const char * name
Pad name.
FILE * avpriv_fopen_utf8(const char *path, const char *mode)
Open a file using a UTF-8 filename.
void * av_calloc(size_t nmemb, size_t size)
@ AV_PIX_FMT_0BGR
packed BGR 8:8:8, 32bpp, XBGRXBGR... X=unused/undefined
double av_strtod(const char *numstr, char **tail)
Parse the string in numstr and return its value as a double.
char * comp_points_str_all
void av_bprintf(AVBPrint *buf, const char *fmt,...)
int h
agreed upon image height
void av_bprint_clear(AVBPrint *buf)
Reset the string to "" but keep internal allocated data.
static int pchip_find_derivatives(const int n, const double *hk, const double *mk, double *dk)
Evalaute the piecewise polynomial derivatives at endpoints.
static struct keypoint * make_point(double x, double y, struct keypoint *next)
#define AV_PIX_FMT_FLAG_PLANAR
At least one pixel component is not in the first data plane.
static int config_input(AVFilterLink *inlink)
@ AV_PIX_FMT_GBRP
planar GBR 4:4:4 24bpp
#define AVFILTER_FLAG_SLICE_THREADS
The filter supports multithreading by splitting frames into multiple parts and processing them concur...
char * av_strdup(const char *s)
Duplicate a string.
#define SET_COMP_IF_NOT_SET(n, name)
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
static av_cold int curves_init(AVFilterContext *ctx)
#define FILTER_OUTPUTS(array)
static int interpolate_pchip(void *log_ctx, uint16_t *y, const struct keypoint *points, int nbits)
Prepare the lookup table by piecewise monotonic cubic interpolation (PCHIP)
static int parse_psfile(AVFilterContext *ctx, const char *fname)
static int parse_points_str(AVFilterContext *ctx, struct keypoint **points, const char *s, int lut_size)
int ff_fill_rgba_map(uint8_t *rgba_map, enum AVPixelFormat pix_fmt)
static double pchip_edge_case(double h0, double h1, double m0, double m1)
Evalaute the derivative of an edge endpoint.
#define flags(name, subs,...)
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
@ AV_PIX_FMT_0RGB
packed RGB 8:8:8, 32bpp, XRGBXRGB... X=unused/undefined
static av_always_inline int ff_filter_execute(AVFilterContext *ctx, avfilter_action_func *func, void *arg, int *ret, int nb_jobs)
static int filter_frame(AVFilterLink *inlink, AVFrame *in)