[vlc-devel] [PATCH 5/9] Make transform filter work with chains where format change is not allowed.

[Rémi Denis-Courmont]

Le mercredi 5 mars 2014, 17:01:26 Matthias Keiser a écrit :
> ---
>  modules/video_filter/transform.c | 67
> +++++++++++++++++++++++----------------- 1 file changed, 38 insertions(+),
> 29 deletions(-)
> 
> diff --git a/modules/video_filter/transform.c
> b/modules/video_filter/transform.c index 60fdaa1..c249521 100644
> --- a/modules/video_filter/transform.c
> +++ b/modules/video_filter/transform.c
> @@ -229,6 +229,7 @@ typedef struct {
>      char      name[16];
>      convert_t convert;
>      convert_t iconvert;
> +    video_transform_t operation;
>      void      (*plane8) (plane_t *dst, const plane_t *src);
>      void      (*plane16)(plane_t *dst, const plane_t *src);
>      void      (*plane32)(plane_t *dst, const plane_t *src);
> @@ -236,18 +237,18 @@ typedef struct {
>      void      (*yuyv)(plane_t *dst, const plane_t *src);
>  } transform_description_t;
> 
> -#define DESC(str, f, invf) \
> -    { str, f, invf, Plane8_##f, Plane16_##f, Plane32_##f, \
> +#define DESC(str, f, invf, op) \
> +    { str, f, invf, op, Plane8_##f, Plane16_##f, Plane32_##f, \
>        Plane422_##f, PlaneYUY2_##f }
> 
>  static const transform_description_t descriptions[] = {
> -    DESC("90",            R90,           R270),
> -    DESC("180",           R180,          R180),
> -    DESC("270",           R270,          R90),
> -    DESC("hflip",         HFlip,         HFlip),
> -    DESC("vflip",         VFlip,         VFlip),
> -    DESC("transpose",     Transpose,     Transpose),
> -    DESC("antitranspose", AntiTranspose, AntiTranspose),
> +    DESC("90",            R90,           R270,          TRANSFORM_R90),
> +    DESC("180",           R180,          R180,          TRANSFORM_R180),
> +    DESC("270",           R270,          R90,           TRANSFORM_R270),
> +    DESC("hflip",         HFlip,         HFlip,         TRANSFORM_HFLIP),
> +    DESC("vflip",         VFlip,         VFlip,         TRANSFORM_VFLIP),
> +    DESC("transpose",     Transpose,     Transpose,    
> TRANSFORM_TRANSPOSE), +    DESC("antitranspose", AntiTranspose,
> AntiTranspose, TRANSFORM_ANTI_TRANSPOSE), };
> 
>  static bool dsc_is_rotated(const transform_description_t *dsc)
> @@ -373,19 +374,38 @@ static int Open(vlc_object_t *object)
>                      }
>              }
>          }
> +    }
> +
> +    /*
> +     * Note: we neither compare nor set dst->orientation,
> +     * the caller needs to do it manually (user might want
> +     * to transform video without changing the orientation).
> +     */

Yeah... I am not sure if we can rely on b_allow_fmt_out_change for this. Did 
you check?

To support hardware accelerated decoding, I think we will need to split the 
transform plugin in two distinct plugins:
- one video conversion plugin for the actual CPU conversion with non-zero 
priority, comparing the orientation of in and out formats, and
- one dummy transform filter that just overrides the orientation of its output 
format based on the user settings.

That way, hardware surfaces can have their own back-end for the rotation in 
hardware. This can be done implemented separately later though.

> +
> +    video_format_t src_trans = *src;
> +    video_format_TransformBy(&src_trans, dsc->operation);
> +
> +    if (!filter->b_allow_fmt_out_change &&
> +        (dst->i_width          != src_trans.i_width ||
> +         dst->i_visible_width  != src_trans.i_visible_width ||
> +         dst->i_height         != src_trans.i_height ||
> +         dst->i_visible_height != src_trans.i_visible_height ||
> +         dst->i_sar_num        != src_trans.i_sar_num ||
> +         dst->i_sar_den        != src_trans.i_sar_den ||
> +         dst->i_x_offset       != src_trans.i_x_offset ||
> +         dst->i_y_offset       != src_trans.i_y_offset)) {
> 
> -        if (!filter->b_allow_fmt_out_change) {
>              msg_Err(filter, "Format change is not allowed");
>              goto error;
>          }
> -
> -        dst->i_width          = src->i_height;
> -        dst->i_visible_width  = src->i_visible_height;
> -        dst->i_height         = src->i_width;
> -        dst->i_visible_height = src->i_visible_width;
> -        dst->i_sar_num        = src->i_sar_den;
> -        dst->i_sar_den        = src->i_sar_num;
> -    }
> +    dst->i_width          = src_trans.i_width;
> +    dst->i_visible_width  = src_trans.i_visible_width;
> +    dst->i_height         = src_trans.i_height;
> +    dst->i_visible_height = src_trans.i_visible_height;
> +    dst->i_sar_num        = src_trans.i_sar_num;
> +    dst->i_sar_den        = src_trans.i_sar_den;
> +    dst->i_x_offset       = src_trans.i_x_offset;
> +    dst->i_y_offset       = src_trans.i_y_offset;
> 
>      /* Deal with weird packed formats */
>      switch (src->i_chroma) {
> @@ -406,17 +426,6 @@ static int Open(vlc_object_t *object)
>              goto error;
>      }
> 
> -    dst->i_x_offset       = INT_MAX;
> -    dst->i_y_offset       = INT_MAX;
> -    for (int i = 0; i < 2; i++) {
> -        int tx, ty;
> -        dsc->iconvert(&tx, &ty, src->i_width, src->i_height,
> -                      src->i_x_offset + i * (src->i_visible_width  - 1),
> -                      src->i_y_offset + i * (src->i_visible_height - 1));
> -        dst->i_x_offset = __MIN(dst->i_x_offset, (unsigned)(1 + tx));
> -        dst->i_y_offset = __MIN(dst->i_y_offset, (unsigned)(1 + ty));
> -    }
> -
>      filter->p_sys           = sys;
>      filter->pf_video_filter = Filter;
>      filter->pf_video_mouse  = Mouse;

-- 
Rémi Denis-Courmont
http://www.remlab.net/