view src/video/directfb/SDL_DirectFB_yuv.c @ 3880:74e828c64315 SDL-1.2

Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents 23fe15f88c03
children 782fd950bd46 c121d94672cb e5a65c16913b
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* This is the DirectFB implementation of YUV video overlays */

#include "SDL_video.h"
#include "SDL_DirectFB_yuv.h"
#include "../SDL_yuvfuncs.h"


/* The functions used to manipulate software video overlays */
static struct private_yuvhwfuncs directfb_yuvfuncs = {
  DirectFB_LockYUVOverlay,
  DirectFB_UnlockYUVOverlay,
  DirectFB_DisplayYUVOverlay,
  DirectFB_FreeYUVOverlay
};

struct private_yuvhwdata {
  DFBDisplayLayerID      layer_id;

  IDirectFBDisplayLayer *layer;
  IDirectFBSurface      *surface;

  /* These are just so we don't have to allocate them separately */
  Uint16 pitches[3];
  Uint8 *planes[3];
};

static DFBEnumerationResult
enum_layers_callback( DFBDisplayLayerID            id,
                      DFBDisplayLayerDescription   desc,
                      void                        *data )
{
  struct private_yuvhwdata *hwdata = (struct private_yuvhwdata *) data;

  /* we don't want the primary */
  if (id == DLID_PRIMARY)
    return DFENUM_OK;

  /* take the one with a surface for video */
  if ((desc.caps & DLCAPS_SURFACE) && (desc.type & DLTF_VIDEO))
    {
      hwdata->layer_id = id;

      return DFENUM_CANCEL;
    }

  return DFENUM_OK;
}


static DFBResult CreateYUVSurface(_THIS, struct private_yuvhwdata *hwdata,
                                  int width, int height, Uint32 format)
{
  DFBResult              ret;
  IDirectFB             *dfb = HIDDEN->dfb;
  IDirectFBDisplayLayer *layer;
  DFBDisplayLayerConfig  conf;

  ret = dfb->EnumDisplayLayers (dfb, enum_layers_callback, hwdata);
  if (ret)
    {
      SetDirectFBerror("IDirectFB::EnumDisplayLayers", ret);
      return ret;
    }

  if (!hwdata->layer_id)
    return DFB_UNSUPPORTED;

  ret = dfb->GetDisplayLayer (dfb, hwdata->layer_id, &layer);
  if (ret)
    {
      SetDirectFBerror("IDirectFB::GetDisplayLayer", ret);
      return ret;
    }

  conf.flags = DLCONF_WIDTH | DLCONF_HEIGHT | DLCONF_PIXELFORMAT;
  conf.width = width;
  conf.height = height;

  switch (format)
    {
    case SDL_YV12_OVERLAY:
      conf.pixelformat = DSPF_YV12;
      break;
    case SDL_IYUV_OVERLAY:
      conf.pixelformat = DSPF_I420;
      break;
    case SDL_YUY2_OVERLAY:
      conf.pixelformat = DSPF_YUY2;
      break;
    case SDL_UYVY_OVERLAY:
      conf.pixelformat = DSPF_UYVY;
      break;
    default:
      fprintf (stderr, "SDL_DirectFB: Unsupported YUV format (0x%08x)!\n", format);
      break;
    }

  ret = layer->SetConfiguration (layer, &conf);
  if (ret)
    {
      SetDirectFBerror("IDirectFBDisplayLayer::SetConfiguration", ret);
      layer->Release (layer);
      return ret;
    }

  ret = layer->GetSurface (layer, &hwdata->surface);
  if (ret)
    {
      SetDirectFBerror("IDirectFBDisplayLayer::GetSurface", ret);
      layer->Release (layer);
      return ret;
    }

  hwdata->layer = layer;

  return DFB_OK;
}

SDL_Overlay *DirectFB_CreateYUVOverlay(_THIS, int width, int height, Uint32 format, SDL_Surface *display)
{
  SDL_Overlay *overlay;
  struct private_yuvhwdata *hwdata;

  /* Create the overlay structure */
  overlay = SDL_calloc (1, sizeof(SDL_Overlay));
  if (!overlay)
    {
      SDL_OutOfMemory();
      return NULL;
    }
	
  /* Fill in the basic members */
  overlay->format = format;
  overlay->w = width;
  overlay->h = height;

  /* Set up the YUV surface function structure */
  overlay->hwfuncs = &directfb_yuvfuncs;

  /* Create the pixel data and lookup tables */
  hwdata = SDL_calloc(1, sizeof(struct private_yuvhwdata));
  overlay->hwdata = hwdata;
  if (!hwdata)
    {
      SDL_OutOfMemory();
      SDL_FreeYUVOverlay (overlay);
      return NULL;
    }

  if (CreateYUVSurface (this, hwdata, width, height, format))
    {
      SDL_FreeYUVOverlay (overlay);
      return NULL;
    }

  overlay->hw_overlay = 1;

  /* Set up the plane pointers */
  overlay->pitches = hwdata->pitches;
  overlay->pixels = hwdata->planes;
  switch (format)
    {
    case SDL_YV12_OVERLAY:
    case SDL_IYUV_OVERLAY:
      overlay->planes = 3;
      break;
    default:
      overlay->planes = 1;
      break;
    }

  /* We're all done.. */
  return overlay;
}

int DirectFB_LockYUVOverlay(_THIS, SDL_Overlay *overlay)
{
  DFBResult         ret;
  void             *data;
  int               pitch;
  IDirectFBSurface *surface = overlay->hwdata->surface;

  ret = surface->Lock (surface, DSLF_READ | DSLF_WRITE, &data, &pitch);
  if (ret)
    {
      SetDirectFBerror("IDirectFBSurface::Lock", ret);
      return -1;
    }

  /* Find the pitch and offset values for the overlay */
  overlay->pitches[0] = (Uint16) pitch;
  overlay->pixels[0]  = (Uint8*) data;

  switch (overlay->format)
    {
    case SDL_YV12_OVERLAY:
    case SDL_IYUV_OVERLAY:
      /* Add the two extra planes */
      overlay->pitches[1] = overlay->pitches[0] / 2;
      overlay->pitches[2] = overlay->pitches[0] / 2;
      overlay->pixels[1]  = overlay->pixels[0] + overlay->pitches[0] * overlay->h;
      overlay->pixels[2]  = overlay->pixels[1] + overlay->pitches[1] * overlay->h / 2;
      break;
    default:
      /* Only one plane, no worries */
      break;
    }

  return 0;
}

void DirectFB_UnlockYUVOverlay(_THIS, SDL_Overlay *overlay)
{
  IDirectFBSurface *surface = overlay->hwdata->surface;

  overlay->pixels[0] = overlay->pixels[1] = overlay->pixels[2] = NULL;

  surface->Unlock (surface);
}

int DirectFB_DisplayYUVOverlay(_THIS, SDL_Overlay *overlay, SDL_Rect *src, SDL_Rect *dst)
{
  DFBResult              ret;
  DFBDisplayLayerConfig  conf;
  IDirectFBDisplayLayer *primary = HIDDEN->layer;
  IDirectFBDisplayLayer *layer   = overlay->hwdata->layer;

  primary->GetConfiguration (primary, &conf);

  ret = layer->SetScreenLocation (layer,
                                  dst->x / (float) conf.width, dst->y / (float) conf.height,
                                  dst->w / (float) conf.width, dst->h / (float) conf.height );
  if (ret)
    {
      SetDirectFBerror("IDirectFBDisplayLayer::SetScreenLocation", ret);
      return -1;
    }

  return 0;
}

void DirectFB_FreeYUVOverlay(_THIS, SDL_Overlay *overlay)
{
  struct private_yuvhwdata *hwdata;

  hwdata = overlay->hwdata;
  if (hwdata)
    {
      if (hwdata->surface)
        hwdata->surface->Release (hwdata->surface);

      if (hwdata->layer)
        hwdata->layer->Release (hwdata->layer);

      free (hwdata);
    }
}