[FFmpeg-devel] [PATCH 4/5] drawutils: new API.
Stefano Sabatini
stefasab at gmail.com
Fri Mar 9 18:36:14 CET 2012
On date Thursday 2012-03-08 14:49:17 +0100, Nicolas George encoded:
> This new API stores useful data in a dedicated structure
> and has clearly delimited init functions.
>
> Hopefully, uses of the old API can be replaced quickly.
>
> Signed-off-by: Nicolas George <nicolas.george at normalesup.org>
> ---
> libavfilter/drawutils.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++
> libavfilter/drawutils.h | 58 +++++++++++++++++++++
> 2 files changed, 188 insertions(+), 0 deletions(-)
>
> diff --git a/libavfilter/drawutils.c b/libavfilter/drawutils.c
> index bf308a1..584cfa6 100644
> --- a/libavfilter/drawutils.c
> +++ b/libavfilter/drawutils.c
> @@ -120,3 +120,133 @@ void ff_copy_rectangle(uint8_t *dst[4], int dst_linesize[4],
> }
> }
> }
> +
> +int ff_draw_init(FFDrawContext *draw, enum PixelFormat format, unsigned flags)
> +{
> + const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[format];
> + const AVComponentDescriptor *c;
> + unsigned i, nb_planes = 0;
> + int pixelstep[MAX_PLANES] = { 0 };
> +
> + if (desc->flags & ~(PIX_FMT_PLANAR | PIX_FMT_RGB))
> + return AVERROR(ENOSYS);
> + for (i = 0; i < desc->nb_components; i++) {
> + c = &desc->comp[i];
> + /* for now, only 8-bits formats */
> + if (c->depth_minus1 != 8 - 1)
> + return AVERROR(ENOSYS);
> + if (c->plane >= MAX_PLANES)
> + return AVERROR(ENOSYS);
> + /* strange interleaving */
> + if (pixelstep[c->plane] != 0 &&
> + pixelstep[c->plane] != c->step_minus1 + 1)
> + return AVERROR(ENOSYS);
> + pixelstep[c->plane] = c->step_minus1 + 1;
> + nb_planes = FFMAX(nb_planes, c->plane + 1);
> + }
> + if ((desc->log2_chroma_w || desc->log2_chroma_h) && nb_planes < 3)
> + return AVERROR(ENOSYS); /* exclude NV12 and NV21 */
> + memset(draw, 0, sizeof(*draw));
> + draw->desc = desc;
> + draw->format = format;
> + draw->nb_planes = nb_planes;
> + memcpy(draw->pixelstep, pixelstep, sizeof(draw->pixelstep));
> + if (nb_planes >= 3 && !(desc->flags & PIX_FMT_RGB)) {
> + draw->hsub[1] = draw->hsub[2] = desc->log2_chroma_w;
> + draw->vsub[1] = draw->vsub[2] = desc->log2_chroma_h;
> + }
> + return 0;
> +}
> +
> +void ff_draw_color(FFDrawContext *draw, FFDrawColor *color, uint8_t rgba[4])
> +{
> + unsigned i;
> + uint8_t rgba_map[4];
> +
> + if ((draw->desc->flags & PIX_FMT_RGB) && draw->nb_planes == 1 &&
> + ff_fill_rgba_map(rgba_map, draw->format) >= 0) {
> + for (i = 0; i < 4; i++)
> + color->comp[0].u8[rgba_map[i]] = rgba[i];
> + } else if (draw->nb_planes == 3 || draw->nb_planes == 4) {
> + /* assume YUV */
> + color->comp[0].u8[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
> + color->comp[1].u8[0] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
> + color->comp[2].u8[0] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
> + color->comp[3].u8[0] = rgba[3];
> + } else {
> + av_log(NULL, AV_LOG_WARNING,
> + "Color conversion not implemented for %s\n", draw->desc->name);
> + memset(color, 128, sizeof(*color));
uhmmm maybe we could create a special logging context for DrawContext,
drop the error message altogether and/or return an error code.
> + }
> +}
> +
> +static uint8_t *pointer_at(FFDrawContext *draw, uint8_t *data[], int linesize[],
> + int plane, int x, int y)
> +{
> + return data[plane] +
> + (y >> draw->vsub[plane]) * linesize[plane] +
> + (x >> draw->hsub[plane]) * draw->pixelstep[plane];
> +}
maybe turn it to a macro or an inline function
> +
> +void ff_copy_rectangle2(FFDrawContext *draw,
> + uint8_t *dst[], int dst_linesize[],
> + uint8_t *src[], int src_linesize[],
> + int dst_x, int dst_y, int src_x, int src_y,
> + int w, int h)
> +{
> + int plane, y, wp, hp;
> + uint8_t *p, *q;
> +
> + for (plane = 0; plane < draw->nb_planes; plane++) {
> + p = pointer_at(draw, src, src_linesize, plane, src_x, src_y);
> + q = pointer_at(draw, dst, dst_linesize, plane, dst_x, dst_y);
> + wp = (w >> draw->hsub[plane]) * draw->pixelstep[plane];
> + hp = (h >> draw->vsub[plane]);
> + for (y = 0; y < hp; y++) {
> + memcpy(q, p, wp);
> + p += src_linesize[plane];
> + q += dst_linesize[plane];
> + }
> + }
> +}
> +
> +void ff_fill_rectangle(FFDrawContext *draw, FFDrawColor *color,
> + uint8_t *dst[], int dst_linesize[],
> + int dst_x, int dst_y, int w, int h)
> +{
> + int plane, x, y, wp, hp;
> + uint8_t *p0, *p;
> +
> + for (plane = 0; plane < draw->nb_planes; plane++) {
> + p0 = pointer_at(draw, dst, dst_linesize, plane, dst_x, dst_y);
> + wp = (w >> draw->hsub[plane]);
> + hp = (h >> draw->vsub[plane]);
> + p = p0;
> + /* copy first line from color */
> + for (x = 0; x < wp; x++) {
> + memcpy(p, color->comp[plane].u8, draw->pixelstep[plane]);
> + p += draw->pixelstep[plane];
> + }
> + wp *= draw->pixelstep[plane];
> + /* copy next lines from first line */
> + p = p0 + dst_linesize[plane];
> + for (y = 1; y < hp; y++) {
> + memcpy(p, p0, wp);
> + p += dst_linesize[plane];
> + }
> + }
> +}
> +
> +AVFilterFormats *ff_draw_supported_pixel_formats(void)
> +{
> + enum PixelFormat i, pix_fmts[PIX_FMT_NB + 1];
> + unsigned n = 0;
> + FFDrawContext draw;
> +
> + for (i = 0; i < PIX_FMT_NB; i++)
> + if (ff_draw_init(&draw, i, 0) >= 0)
> + pix_fmts[n++] = i;
> + pix_fmts[n++] = PIX_FMT_NONE;
> + return avfilter_make_format_list(pix_fmts);
> +}
> +
> diff --git a/libavfilter/drawutils.h b/libavfilter/drawutils.h
> index 330b1cb..58448b8 100644
> --- a/libavfilter/drawutils.h
> +++ b/libavfilter/drawutils.h
> @@ -25,6 +25,7 @@
> */
>
> #include <stdint.h>
> +#include "avfilter.h"
> #include "libavutil/pixfmt.h"
>
> int ff_fill_rgba_map(uint8_t *rgba_map, enum PixelFormat pix_fmt);
> @@ -42,4 +43,61 @@ void ff_copy_rectangle(uint8_t *dst[4], int dst_linesize[4],
> uint8_t *src[4], int src_linesize[4], int pixelstep[4],
> int hsub, int vsub, int x, int y, int y2, int w, int h);
>
> +#define MAX_PLANES 4
> +
> +typedef struct FFDrawContext {
> + const struct AVPixFmtDescriptor *desc;
> + enum PixelFormat format;
> + unsigned nb_planes;
> + int pixelstep[MAX_PLANES]; /*< offset between pixels */
> + uint8_t hsub[MAX_PLANES]; /*< horizontal subsamling */
> + uint8_t vsub[MAX_PLANES]; /*< vertical subsamling */
> +} FFDrawContext;
> +
> +typedef struct FFDrawColor {
> + union {
> + uint32_t u32;
> + uint16_t u16;
> + uint8_t u8[4];
> + } comp[MAX_PLANES];
> +} FFDrawColor;
> +
> +/**
> + * Init a draw context.
Add something along the lines of:
Only a limited number of pixel formats is supported, if format is not
supported the function will return an error.
> + *
> + * No flags currently defined.
> + * @return 0 for success, < 0 for error
> + */
> +int ff_draw_init(FFDrawContext *draw, enum PixelFormat format, unsigned flags);
> +
> +/**
> + * Prepare a color.
> + */
> +void ff_draw_color(FFDrawContext *draw, FFDrawColor *color, uint8_t rgba[4]);
> +
> +/**
> + * Copy a rectangle from an image to another.
> + *
> + * The coordinates must be as even as the subsampling requires.
> + */
> +void ff_copy_rectangle2(FFDrawContext *draw,
> + uint8_t *dst[], int dst_linesize[],
> + uint8_t *src[], int src_linesize[],
> + int dst_x, int dst_y, int src_x, int src_y,
> + int w, int h);
> +
> +/**
> + * Copy a rectangle from an image to another.
copy&paste error
Mention how to "prepare" a color.
> + *
> + * The coordinates must be as even as the subsampling requires.
> + */
> +void ff_fill_rectangle(FFDrawContext *draw, FFDrawColor *color,
> + uint8_t *dst[], int dst_linesize[],
> + int dst_x, int dst_y, int w, int h);
> +
> +/**
> + * Return the list of pixel formats supported by the draw functions.
> + */
> +AVFilterFormats *ff_draw_supported_pixel_formats(void);
> +
> #endif /* AVFILTER_DRAWUTILS_H */
Looks fine otherwise, but testing this new API with FATE before to
commit it may help to spot eventual errors.
--
FFmpeg = Fantastic Faithless Merciful Pure Eccentric Gladiator
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