imgconvert.c

现在关于h.264的源码很多

/*
 * Misc image convertion routines
 * Copyright (c) 2001, 2002, 2003 Fabrice Bellard.
 *
 * 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 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 Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file imgconvert.c
 * Misc image convertion routines.
 */

/* TODO:
 * - write 'ffimg' program to test all the image related stuff
 * - move all api to slice based system
 * - integrate deinterlacing, postprocessing and scaling in the conversion process
 */

#include "avcodec.h"
#include "dsputil.h"

#ifdef USE_FASTMEMCPY
#include "fastmemcpy.h"
#endif

#ifdef HAVE_MMX
#include "i386/mmx.h"
#endif

#define xglue(x, y) x ## y
#define glue(x, y) xglue(x, y)

#define FF_COLOR_RGB      0 /* RGB color space */
#define FF_COLOR_GRAY     1 /* gray color space */
#define FF_COLOR_YUV      2 /* YUV color space. 16 <= Y <= 235, 16 <= U, V <= 240 */
#define FF_COLOR_YUV_JPEG 3 /* YUV color space. 0 <= Y <= 255, 0 <= U, V <= 255 */

#define FF_PIXEL_PLANAR   0 /* each channel has one component in AVPicture */
#define FF_PIXEL_PACKED   1 /* only one components containing all the channels */
#define FF_PIXEL_PALETTE  2  /* one components containing indexes for a palette */

typedef struct PixFmtInfo {
    const char *name;
    uint8_t nb_channels;     /* number of channels (including alpha) */
    uint8_t color_type;      /* color type (see FF_COLOR_xxx constants) */
    uint8_t pixel_type;      /* pixel storage type (see FF_PIXEL_xxx constants) */
    uint8_t is_alpha : 1;    /* true if alpha can be specified */
    uint8_t x_chroma_shift;  /* X chroma subsampling factor is 2 ^ shift */
    uint8_t y_chroma_shift;  /* Y chroma subsampling factor is 2 ^ shift */
    uint8_t depth;           /* bit depth of the color components */
} PixFmtInfo;

/* this table gives more information about formats */
static PixFmtInfo pix_fmt_info[PIX_FMT_NB] = {
    /* YUV formats */
    [PIX_FMT_YUV420P] = {
        .name = "yuv420p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 1,
    },
    [PIX_FMT_YUV422P] = {
        .name = "yuv422p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 0,
    },
    [PIX_FMT_YUV444P] = {
        .name = "yuv444p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_YUV422] = {
        .name = "yuv422",
        .nb_channels = 1,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 0,
    },
    [PIX_FMT_UYVY422] = {
        .name = "uyvy422",
        .nb_channels = 1,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 0,
    },
    [PIX_FMT_YUV410P] = {
        .name = "yuv410p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 2, .y_chroma_shift = 2,
    },
    [PIX_FMT_YUV411P] = {
        .name = "yuv411p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 2, .y_chroma_shift = 0,
    },

    /* JPEG YUV */
    [PIX_FMT_YUVJ420P] = {
        .name = "yuvj420p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV_JPEG,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 1,
    },
    [PIX_FMT_YUVJ422P] = {
        .name = "yuvj422p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV_JPEG,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 0,
    },
    [PIX_FMT_YUVJ444P] = {
        .name = "yuvj444p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV_JPEG,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },

    /* RGB formats */
    [PIX_FMT_RGB24] = {
        .name = "rgb24",
        .nb_channels = 3,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_BGR24] = {
        .name = "bgr24",
        .nb_channels = 3,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_RGBA32] = {
        .name = "rgba32",
        .nb_channels = 4, .is_alpha = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_RGB565] = {
        .name = "rgb565",
        .nb_channels = 3,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 5,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_RGB555] = {
        .name = "rgb555",
        .nb_channels = 4, .is_alpha = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 5,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },

    /* gray / mono formats */
    [PIX_FMT_GRAY8] = {
        .name = "gray",
        .nb_channels = 1,
        .color_type = FF_COLOR_GRAY,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
    },
    [PIX_FMT_MONOWHITE] = {
        .name = "monow",
        .nb_channels = 1,
        .color_type = FF_COLOR_GRAY,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 1,
    },
    [PIX_FMT_MONOBLACK] = {
        .name = "monob",
        .nb_channels = 1,
        .color_type = FF_COLOR_GRAY,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 1,
    },

    /* paletted formats */
    [PIX_FMT_PAL8] = {
        .name = "pal8",
        .nb_channels = 4, .is_alpha = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PALETTE,
        .depth = 8,
    },
    [PIX_FMT_XVMC_MPEG2_MC] = {
        .name = "xvmcmc",
    },
    [PIX_FMT_XVMC_MPEG2_IDCT] = {
        .name = "xvmcidct",
    },
    [PIX_FMT_UYVY411] = {
        .name = "uyvy411",
        .nb_channels = 1,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 2, .y_chroma_shift = 0,
    },
};

void avcodec_get_chroma_sub_sample(int pix_fmt, int *h_shift, int *v_shift)
{
    *h_shift = pix_fmt_info[pix_fmt].x_chroma_shift;
    *v_shift = pix_fmt_info[pix_fmt].y_chroma_shift;
}

const char *avcodec_get_pix_fmt_name(int pix_fmt)
{
    if (pix_fmt < 0 || pix_fmt >= PIX_FMT_NB)
        return "???";
    else
        return pix_fmt_info[pix_fmt].name;
}

enum PixelFormat avcodec_get_pix_fmt(const char* name)
{
    int i;

    for (i=0; i < PIX_FMT_NB; i++)
         if (!strcmp(pix_fmt_info[i].name, name))
             break;
    return i;
}

/* Picture field are filled with 'ptr' addresses. Also return size */
int avpicture_fill(AVPicture *picture, uint8_t *ptr,
                   int pix_fmt, int width, int height)
{
    int size, w2, h2, size2;
    PixFmtInfo *pinfo;

    if(avcodec_check_dimensions(NULL, width, height))
        goto fail;

    pinfo = &pix_fmt_info[pix_fmt];
    size = width * height;
    switch(pix_fmt) {
    case PIX_FMT_YUV420P:
    case PIX_FMT_YUV422P:
    case PIX_FMT_YUV444P:
    case PIX_FMT_YUV410P:
    case PIX_FMT_YUV411P:
    case PIX_FMT_YUVJ420P:
    case PIX_FMT_YUVJ422P:
    case PIX_FMT_YUVJ444P:
        w2 = (width + (1 << pinfo->x_chroma_shift) - 1) >> pinfo->x_chroma_shift;
        h2 = (height + (1 << pinfo->y_chroma_shift) - 1) >> pinfo->y_chroma_shift;
        size2 = w2 * h2;
        picture->data[0] = ptr;
        picture->data[1] = picture->data[0] + size;
        picture->data[2] = picture->data[1] + size2;
        picture->linesize[0] = width;
        picture->linesize[1] = w2;
        picture->linesize[2] = w2;
        return size + 2 * size2;
    case PIX_FMT_RGB24:
    case PIX_FMT_BGR24:
        picture->data[0] = ptr;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->linesize[0] = width * 3;
        return size * 3;
    case PIX_FMT_RGBA32:
        picture->data[0] = ptr;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->linesize[0] = width * 4;
        return size * 4;
    case PIX_FMT_RGB555:
    case PIX_FMT_RGB565:
    case PIX_FMT_YUV422:
        picture->data[0] = ptr;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->linesize[0] = width * 2;
        return size * 2;
    case PIX_FMT_UYVY422:
        picture->data[0] = ptr;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->linesize[0] = width * 2;
        return size * 2;
    case PIX_FMT_UYVY411:
        picture->data[0] = ptr;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->linesize[0] = width + width/2;
        return size + size/2;
    case PIX_FMT_GRAY8:
        picture->data[0] = ptr;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->linesize[0] = width;
        return size;
    case PIX_FMT_MONOWHITE:
    case PIX_FMT_MONOBLACK:
        picture->data[0] = ptr;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->linesize[0] = (width + 7) >> 3;
        return picture->linesize[0] * height;
    case PIX_FMT_PAL8:
        size2 = (size + 3) & ~3;
        picture->data[0] = ptr;
        picture->data[1] = ptr + size2; /* palette is stored here as 256 32 bit words */
        picture->data[2] = NULL;
        picture->linesize[0] = width;
        picture->linesize[1] = 4;
        return size2 + 256 * 4;
    default:
fail:
        picture->data[0] = NULL;
        picture->data[1] = NULL;
        picture->data[2] = NULL;
        picture->data[3] = NULL;
        return -1;
    }
}

int avpicture_layout(const AVPicture* src, int pix_fmt, int width, int height,
                     unsigned char *dest, int dest_size)
{
    PixFmtInfo* pf = &pix_fmt_info[pix_fmt];
    int i, j, w, h, data_planes;
    const unsigned char* s;
    int size = avpicture_get_size(pix_fmt, width, height);

    if (size > dest_size || size < 0)
        return -1;

    if (pf->pixel_type == FF_PIXEL_PACKED || pf->pixel_type == FF_PIXEL_PALETTE) {
        if (pix_fmt == PIX_FMT_YUV422 ||
            pix_fmt == PIX_FMT_UYVY422 ||
            pix_fmt == PIX_FMT_RGB565 ||
            pix_fmt == PIX_FMT_RGB555)
            w = width * 2;
        else if (pix_fmt == PIX_FMT_UYVY411)
          w = width + width/2;
        else if (pix_fmt == PIX_FMT_PAL8)
          w = width;
        else
          w = width * (pf->depth * pf->nb_channels / 8);

        data_planes = 1;
        h = height;
    } else {
        data_planes = pf->nb_channels;
        w = (width*pf->depth + 7)/8;
        h = height;
    }

    for (i=0; i<data_planes; i++) {
         if (i == 1) {
             w = width >> pf->x_chroma_shift;
             h = height >> pf->y_chroma_shift;
         }
         s = src->data[i];
         for(j=0; j<h; j++) {
             memcpy(dest, s, w);
             dest += w;
             s += src->linesize[i];
         }
    }

    if (pf->pixel_type == FF_PIXEL_PALETTE)
        memcpy((unsigned char *)(((size_t)dest + 3) & ~3), src->data[1], 256 * 4);

    return size;
}

int avpicture_get_size(int pix_fmt, int width, int height)
{
    AVPicture dummy_pict;
    return avpicture_fill(&dummy_pict, NULL, pix_fmt, width, height);
}

/**
 * compute the loss when converting from a pixel format to another
 */
int avcodec_get_pix_fmt_loss(int dst_pix_fmt, int src_pix_fmt,
                             int has_alpha)
{
    const PixFmtInfo *pf, *ps;
    int loss;

    ps = &pix_fmt_info[src_pix_fmt];
    pf = &pix_fmt_info[dst_pix_fmt];

    /* compute loss */
    loss = 0;
    pf = &pix_fmt_info[dst_pix_fmt];
    if (pf->depth < ps->depth ||
        (dst_pix_fmt == PIX_FMT_RGB555 && src_pix_fmt == PIX_FMT_RGB565))
        loss |= FF_LOSS_DEPTH;
    if (pf->x_chroma_shift > ps->x_chroma_shift ||
        pf->y_chroma_shift > ps->y_chroma_shift)
        loss |= FF_LOSS_RESOLUTION;
    switch(pf->color_type) {
    case FF_COLOR_RGB:
        if (ps->color_type != FF_COLOR_RGB &&
            ps->color_type != FF_COLOR_GRAY)
            loss |= FF_LOSS_COLORSPACE;
        break;
    case FF_COLOR_GRAY:
        if (ps->color_type != FF_COLOR_GRAY)
            loss |= FF_LOSS_COLORSPACE;
        break;
    case FF_COLOR_YUV:
        if (ps->color_type != FF_COLOR_YUV)
            loss |= FF_LOSS_COLORSPACE;
        break;
    case FF_COLOR_YUV_JPEG:
        if (ps->color_type != FF_COLOR_YUV_JPEG &&
            ps->color_type != FF_COLOR_YUV &&
            ps->color_type != FF_COLOR_GRAY)
            loss |= FF_LOSS_COLORSPACE;
        break;
    default:
        /* fail safe test */
        if (ps->color_type != pf->color_type)
            loss |= FF_LOSS_COLORSPACE;
        break;
    }
    if (pf->color_type == FF_COLOR_GRAY &&
        ps->color_type != FF_COLOR_GRAY)
        loss |= FF_LOSS_CHROMA;
    if (!pf->is_alpha && (ps->is_alpha && has_alpha))
        loss |= FF_LOSS_ALPHA;
    if (pf->pixel_type == FF_PIXEL_PALETTE &&
        (ps->pixel_type != FF_PIXEL_PALETTE && ps->color_type != FF_COLOR_GRAY))
        loss |= FF_LOSS_COLORQUANT;
    return loss;
}

static int avg_bits_per_pixel(int pix_fmt)
{
    int bits;
    const PixFmtInfo *pf;

    pf = &pix_fmt_info[pix_fmt];
    switch(pf->pixel_type) {
    case FF_PIXEL_PACKED:
        switch(pix_fmt) {