imgconvert.c

ffmpeg的完整源代码和作者自己写的文档。不但有在Linux的工程哦

/*
 * Misc image conversion routines
 * Copyright (c) 2001, 2002, 2003 Fabrice Bellard.
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file imgconvert.c
 * misc image conversion 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"
#include "colorspace.h"

#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 const 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_YUYV422] = {
        .name = "yuyv422",
        .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,
    },
    [PIX_FMT_YUV440P] = {
        .name = "yuv440p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 1,
    },

    /* YUV formats with alpha plane */
    [PIX_FMT_YUVA420P] = {
        .name = "yuva420p",
        .nb_channels = 4,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 1,
    },

    /* 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,
    },
    [PIX_FMT_YUVJ440P] = {
        .name = "yuvj440p",
        .nb_channels = 3,
        .color_type = FF_COLOR_YUV_JPEG,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 1,
    },

    /* 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_RGB32] = {
        .name = "rgb32",
        .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 = 3,
        .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_GRAY16BE] = {
        .name = "gray16be",
        .nb_channels = 1,
        .color_type = FF_COLOR_GRAY,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 16,
    },
    [PIX_FMT_GRAY16LE] = {
        .name = "gray16le",
        .nb_channels = 1,
        .color_type = FF_COLOR_GRAY,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 16,
    },
    [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_UYYVYY411] = {
        .name = "uyyvyy411",
        .nb_channels = 1,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 2, .y_chroma_shift = 0,
    },
    [PIX_FMT_BGR32] = {
        .name = "bgr32",
        .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_BGR565] = {
        .name = "bgr565",
        .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_BGR555] = {
        .name = "bgr555",
        .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_RGB8] = {
        .name = "rgb8",
        .nb_channels = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_RGB4] = {
        .name = "rgb4",
        .nb_channels = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 4,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_RGB4_BYTE] = {
        .name = "rgb4_byte",
        .nb_channels = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_BGR8] = {
        .name = "bgr8",
        .nb_channels = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_BGR4] = {
        .name = "bgr4",
        .nb_channels = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 4,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_BGR4_BYTE] = {
        .name = "bgr4_byte",
        .nb_channels = 1,
        .color_type = FF_COLOR_RGB,
        .pixel_type = FF_PIXEL_PACKED,
        .depth = 8,
        .x_chroma_shift = 0, .y_chroma_shift = 0,
    },
    [PIX_FMT_NV12] = {
        .name = "nv12",
        .nb_channels = 2,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 1,
    },
    [PIX_FMT_NV21] = {
        .name = "nv12",
        .nb_channels = 2,
        .color_type = FF_COLOR_YUV,
        .pixel_type = FF_PIXEL_PLANAR,
        .depth = 8,
        .x_chroma_shift = 1, .y_chroma_shift = 1,
    },

    [PIX_FMT_BGR32_1] = {
        .name = "bgr32_1",
        .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_RGB32_1] = {
        .name = "rgb32_1",
        .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,
    },
};

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;
}

void avcodec_pix_fmt_string (char *buf, int buf_size, int pix_fmt)
{
    PixFmtInfo info= pix_fmt_info[pix_fmt];

    char is_alpha_char= info.is_alpha ? 'y' : 'n';

    /* print header */
    if (pix_fmt < 0)
        snprintf (buf, buf_size,
                  "name      " " nb_channels" " depth" " is_alpha"
            );
    else
        snprintf (buf, buf_size,
                  "%-10s" "      %1d     " "   %2d " "     %c   ",
                  info.name,
                  info.nb_channels,
                  info.depth,
                  is_alpha_char
            );
}

int avpicture_fill(AVPicture *picture, uint8_t *ptr,
                   int pix_fmt, int width, int height)
{
    int size, w2, h2, size2;
    const 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_YUV440P:
    case PIX_FMT_YUVJ420P:
    case PIX_FMT_YUVJ422P:
    case PIX_FMT_YUVJ444P:
    case PIX_FMT_YUVJ440P:
        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->data[3] = NULL;
        picture->linesize[0] = width;
        picture->linesize[1] = w2;
        picture->linesize[2] = w2;
        picture->linesize[3] = 0;
        return size + 2 * size2;
    case PIX_FMT_YUVA420P:
        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->data[3] = picture->data[1] + size2 + size2;
        picture->linesize[0] = width;
        picture->linesize[1] = w2;
        picture->linesize[2] = w2;