imgconvert.c

现在关于h.264的源码很多

        [PIX_FMT_RGB24] = {
            .convert = pal8_to_rgb24
        },
        [PIX_FMT_RGBA32] = {
            .convert = pal8_to_rgba32
        },
    },
    [PIX_FMT_UYVY411] = {
        [PIX_FMT_YUV411P] = {
            .convert = uyvy411_to_yuv411p,
        },
    },

};

int avpicture_alloc(AVPicture *picture,
                           int pix_fmt, int width, int height)
{
    unsigned int size;
    void *ptr;

    size = avpicture_get_size(pix_fmt, width, height);
    if(size<0)
        goto fail;
    ptr = av_malloc(size);
    if (!ptr)
        goto fail;
    avpicture_fill(picture, ptr, pix_fmt, width, height);
    return 0;
 fail:
    memset(picture, 0, sizeof(AVPicture));
    return -1;
}

void avpicture_free(AVPicture *picture)
{
    av_free(picture->data[0]);
}

/* return true if yuv planar */
static inline int is_yuv_planar(PixFmtInfo *ps)
{
    return (ps->color_type == FF_COLOR_YUV ||
            ps->color_type == FF_COLOR_YUV_JPEG) &&
        ps->pixel_type == FF_PIXEL_PLANAR;
}

/**
 * Crop image top and left side
 */
int img_crop(AVPicture *dst, const AVPicture *src,
              int pix_fmt, int top_band, int left_band)
{
    int y_shift;
    int x_shift;

    if (pix_fmt < 0 || pix_fmt >= PIX_FMT_NB || !is_yuv_planar(&pix_fmt_info[pix_fmt]))
        return -1;

    y_shift = pix_fmt_info[pix_fmt].y_chroma_shift;
    x_shift = pix_fmt_info[pix_fmt].x_chroma_shift;

    dst->data[0] = src->data[0] + (top_band * src->linesize[0]) + left_band;
    dst->data[1] = src->data[1] + ((top_band >> y_shift) * src->linesize[1]) + (left_band >> x_shift);
    dst->data[2] = src->data[2] + ((top_band >> y_shift) * src->linesize[2]) + (left_band >> x_shift);

    dst->linesize[0] = src->linesize[0];
    dst->linesize[1] = src->linesize[1];
    dst->linesize[2] = src->linesize[2];
    return 0;
}

/* XXX: always use linesize. Return -1 if not supported */
int img_convert(AVPicture *dst, int dst_pix_fmt,
                const AVPicture *src, int src_pix_fmt,
                int src_width, int src_height)
{
    static int inited;
    int i, ret, dst_width, dst_height, int_pix_fmt;
    PixFmtInfo *src_pix, *dst_pix;
    ConvertEntry *ce;
    AVPicture tmp1, *tmp = &tmp1;

    if (src_pix_fmt < 0 || src_pix_fmt >= PIX_FMT_NB ||
        dst_pix_fmt < 0 || dst_pix_fmt >= PIX_FMT_NB)
        return -1;
    if (src_width <= 0 || src_height <= 0)
        return 0;

    if (!inited) {
        inited = 1;
        img_convert_init();
    }

    dst_width = src_width;
    dst_height = src_height;

    dst_pix = &pix_fmt_info[dst_pix_fmt];
    src_pix = &pix_fmt_info[src_pix_fmt];
    if (src_pix_fmt == dst_pix_fmt) {
        /* no conversion needed: just copy */
        img_copy(dst, src, dst_pix_fmt, dst_width, dst_height);
        return 0;
    }

    ce = &convert_table[src_pix_fmt][dst_pix_fmt];
    if (ce->convert) {
        /* specific conversion routine */
        ce->convert(dst, src, dst_width, dst_height);
        return 0;
    }

    /* gray to YUV */
    if (is_yuv_planar(dst_pix) &&
        src_pix_fmt == PIX_FMT_GRAY8) {
        int w, h, y;
        uint8_t *d;

        if (dst_pix->color_type == FF_COLOR_YUV_JPEG) {
            ff_img_copy_plane(dst->data[0], dst->linesize[0],
                     src->data[0], src->linesize[0],
                     dst_width, dst_height);
        } else {
            img_apply_table(dst->data[0], dst->linesize[0],
                            src->data[0], src->linesize[0],
                            dst_width, dst_height,
                            y_jpeg_to_ccir);
        }
        /* fill U and V with 128 */
        w = dst_width;
        h = dst_height;
        w >>= dst_pix->x_chroma_shift;
        h >>= dst_pix->y_chroma_shift;
        for(i = 1; i <= 2; i++) {
            d = dst->data[i];
            for(y = 0; y< h; y++) {
                memset(d, 128, w);
                d += dst->linesize[i];
            }
        }
        return 0;
    }

    /* YUV to gray */
    if (is_yuv_planar(src_pix) &&
        dst_pix_fmt == PIX_FMT_GRAY8) {
        if (src_pix->color_type == FF_COLOR_YUV_JPEG) {
            ff_img_copy_plane(dst->data[0], dst->linesize[0],
                     src->data[0], src->linesize[0],
                     dst_width, dst_height);
        } else {
            img_apply_table(dst->data[0], dst->linesize[0],
                            src->data[0], src->linesize[0],
                            dst_width, dst_height,
                            y_ccir_to_jpeg);
        }
        return 0;
    }

    /* YUV to YUV planar */
    if (is_yuv_planar(dst_pix) && is_yuv_planar(src_pix)) {
        int x_shift, y_shift, w, h, xy_shift;
        void (*resize_func)(uint8_t *dst, int dst_wrap,
                            const uint8_t *src, int src_wrap,
                            int width, int height);

        /* compute chroma size of the smallest dimensions */
        w = dst_width;
        h = dst_height;
        if (dst_pix->x_chroma_shift >= src_pix->x_chroma_shift)
            w >>= dst_pix->x_chroma_shift;
        else
            w >>= src_pix->x_chroma_shift;
        if (dst_pix->y_chroma_shift >= src_pix->y_chroma_shift)
            h >>= dst_pix->y_chroma_shift;
        else
            h >>= src_pix->y_chroma_shift;

        x_shift = (dst_pix->x_chroma_shift - src_pix->x_chroma_shift);
        y_shift = (dst_pix->y_chroma_shift - src_pix->y_chroma_shift);
        xy_shift = ((x_shift & 0xf) << 4) | (y_shift & 0xf);
        /* there must be filters for conversion at least from and to
           YUV444 format */
        switch(xy_shift) {
        case 0x00:
            resize_func = ff_img_copy_plane;
            break;
        case 0x10:
            resize_func = shrink21;
            break;
        case 0x20:
            resize_func = shrink41;
            break;
        case 0x01:
            resize_func = shrink12;
            break;
        case 0x11:
            resize_func = ff_shrink22;
            break;
        case 0x22:
            resize_func = ff_shrink44;
            break;
        case 0xf0:
            resize_func = grow21;
            break;
        case 0xe0:
            resize_func = grow41;
            break;
        case 0xff:
            resize_func = grow22;
            break;
        case 0xee:
            resize_func = grow44;
            break;
        case 0xf1:
            resize_func = conv411;
            break;
        default:
            /* currently not handled */
            goto no_chroma_filter;
        }

        ff_img_copy_plane(dst->data[0], dst->linesize[0],
                       src->data[0], src->linesize[0],
                       dst_width, dst_height);

        for(i = 1;i <= 2; i++)
            resize_func(dst->data[i], dst->linesize[i],
                        src->data[i], src->linesize[i],
                        dst_width>>dst_pix->x_chroma_shift, dst_height>>dst_pix->y_chroma_shift);
        /* if yuv color space conversion is needed, we do it here on
           the destination image */
        if (dst_pix->color_type != src_pix->color_type) {
            const uint8_t *y_table, *c_table;
            if (dst_pix->color_type == FF_COLOR_YUV) {
                y_table = y_jpeg_to_ccir;
                c_table = c_jpeg_to_ccir;
            } else {
                y_table = y_ccir_to_jpeg;
                c_table = c_ccir_to_jpeg;
            }
            img_apply_table(dst->data[0], dst->linesize[0],
                            dst->data[0], dst->linesize[0],
                            dst_width, dst_height,
                            y_table);

            for(i = 1;i <= 2; i++)
                img_apply_table(dst->data[i], dst->linesize[i],
                                dst->data[i], dst->linesize[i],
                                dst_width>>dst_pix->x_chroma_shift,
                                dst_height>>dst_pix->y_chroma_shift,
                                c_table);
        }
        return 0;
    }
 no_chroma_filter:

    /* try to use an intermediate format */
    if (src_pix_fmt == PIX_FMT_YUV422 ||
        dst_pix_fmt == PIX_FMT_YUV422) {
        /* specific case: convert to YUV422P first */
        int_pix_fmt = PIX_FMT_YUV422P;
    } else if (src_pix_fmt == PIX_FMT_UYVY422 ||
        dst_pix_fmt == PIX_FMT_UYVY422) {
        /* specific case: convert to YUV422P first */
        int_pix_fmt = PIX_FMT_YUV422P;
    } else if (src_pix_fmt == PIX_FMT_UYVY411 ||
        dst_pix_fmt == PIX_FMT_UYVY411) {
        /* specific case: convert to YUV411P first */
        int_pix_fmt = PIX_FMT_YUV411P;
    } else if ((src_pix->color_type == FF_COLOR_GRAY &&
                src_pix_fmt != PIX_FMT_GRAY8) ||
               (dst_pix->color_type == FF_COLOR_GRAY &&
                dst_pix_fmt != PIX_FMT_GRAY8)) {
        /* gray8 is the normalized format */
        int_pix_fmt = PIX_FMT_GRAY8;
    } else if ((is_yuv_planar(src_pix) &&
                src_pix_fmt != PIX_FMT_YUV444P &&
                src_pix_fmt != PIX_FMT_YUVJ444P)) {
        /* yuv444 is the normalized format */
        if (src_pix->color_type == FF_COLOR_YUV_JPEG)
            int_pix_fmt = PIX_FMT_YUVJ444P;
        else
            int_pix_fmt = PIX_FMT_YUV444P;
    } else if ((is_yuv_planar(dst_pix) &&
                dst_pix_fmt != PIX_FMT_YUV444P &&
                dst_pix_fmt != PIX_FMT_YUVJ444P)) {
        /* yuv444 is the normalized format */
        if (dst_pix->color_type == FF_COLOR_YUV_JPEG)
            int_pix_fmt = PIX_FMT_YUVJ444P;
        else
            int_pix_fmt = PIX_FMT_YUV444P;
    } else {
        /* the two formats are rgb or gray8 or yuv[j]444p */
        if (src_pix->is_alpha && dst_pix->is_alpha)
            int_pix_fmt = PIX_FMT_RGBA32;
        else
            int_pix_fmt = PIX_FMT_RGB24;
    }
    if (avpicture_alloc(tmp, int_pix_fmt, dst_width, dst_height) < 0)
        return -1;
    ret = -1;
    if (img_convert(tmp, int_pix_fmt,
                    src, src_pix_fmt, src_width, src_height) < 0)
        goto fail1;
    if (img_convert(dst, dst_pix_fmt,
                    tmp, int_pix_fmt, dst_width, dst_height) < 0)
        goto fail1;
    ret = 0;
 fail1:
    avpicture_free(tmp);
    return ret;
}

/* NOTE: we scan all the pixels to have an exact information */
static int get_alpha_info_pal8(const AVPicture *src, int width, int height)
{
    const unsigned char *p;
    int src_wrap, ret, x, y;
    unsigned int a;
    uint32_t *palette = (uint32_t *)src->data[1];

    p = src->data[0];
    src_wrap = src->linesize[0] - width;
    ret = 0;
    for(y=0;y<height;y++) {
        for(x=0;x<width;x++) {
            a = palette[p[0]] >> 24;
            if (a == 0x00) {
                ret |= FF_ALPHA_TRANSP;
            } else if (a != 0xff) {
                ret |= FF_ALPHA_SEMI_TRANSP;
            }
            p++;
        }
        p += src_wrap;
    }
    return ret;
}

/**
 * Tell if an image really has transparent alpha values.
 * @return ored mask of FF_ALPHA_xxx constants
 */
int img_get_alpha_info(const AVPicture *src,
                       int pix_fmt, int width, int height)
{
    PixFmtInfo *pf = &pix_fmt_info[pix_fmt];
    int ret;

    pf = &pix_fmt_info[pix_fmt];
    /* no alpha can be represented in format */
    if (!pf->is_alpha)
        return 0;
    switch(pix_fmt) {
    case PIX_FMT_RGBA32:
        ret = get_alpha_info_rgba32(src, width, height);
        break;
    case PIX_FMT_RGB555:
        ret = get_alpha_info_rgb555(src, width, height);
        break;
    case PIX_FMT_PAL8:
        ret = get_alpha_info_pal8(src, width, height);
        break;
    default:
        /* we do not know, so everything is indicated */
        ret = FF_ALPHA_TRANSP | FF_ALPHA_SEMI_TRANSP;
        break;
    }
    return ret;
}

#ifdef HAVE_MMX
#define DEINT_INPLACE_LINE_LUM \
                    movd_m2r(lum_m4[0],mm0);\
                    movd_m2r(lum_m3[0],mm1);\
                    movd_m2r(lum_m2[0],mm2);\
                    movd_m2r(lum_m1[0],mm3);\
                    movd_m2r(lum[0],mm4);\
                    punpcklbw_r2r(mm7,mm0);\
                    movd_r2m(mm2,lum_m4[0]);\
                    punpcklbw_r2r(mm7,mm1);\
                    punpcklbw_r2r(mm7,mm2);\
                    punpcklbw_r2r(mm7,mm3);\
                    punpcklbw_r2r(mm7,mm4);\
                    paddw_r2r(mm3,mm1);\
                    psllw_i2r(1,mm2);\
                    paddw_r2r(mm4,mm0);\
                    psllw_i2r(2,mm1);\
                    paddw_r2r(mm6,mm2);\
                    paddw_r2r(mm2,mm1);\
                    psubusw_r2r(mm0,mm1);\
                    psrlw_i2r(3,mm1);\
                    packuswb_r2r(mm7,mm1);\
                    movd_r2m(mm1,lum_m2[0]);

#define DEINT_LINE_LUM \
                    movd_m2r(lum_m4[0],mm0);\
                    movd_m2r(lum_m3[0],mm1);\
                    movd_m2r(lum_m2[0],mm2);\
                    movd_m2r(lum_m1[0],mm3);\
                    movd_m2r(lum[0],mm4);\
                    punpcklbw_r2r(mm7,mm0);\
                    punpcklbw_r2r(mm7,mm1);\
                    punpcklbw_r2r(mm7,mm2);\
                    punpcklbw_r2r(mm7,mm3);\
                    punpcklbw_r2r(mm7,mm4);\
                    paddw_r2r(mm3,mm1);\
                    psllw_i2r(1,mm2);\
                    paddw_r2r(mm4,mm0);\
                    psllw_i2r(2,mm1);\
                    paddw_r2r(mm6,mm2);\
                    paddw_r2r(mm2,mm1);\
                    psubusw_r2r(mm0,mm1);\
                    psrlw_i2r(3,mm1);\
                    packuswb_r2r(mm7,mm1);\
                    movd_r2m(mm1,dst[0]);
#endif

/* filter parameters: [-1 4 2 4 -1] // 8 */
static void deinterlace_line(uint8_t *dst,
                             const uint8_t *lum_m4, const uint8_t *lum_m3,
                             const uint8_t *lum_m2, const uint8_t *lum_m1,
                             const uint8_t *lum,
                             int size)
{
#ifndef HAVE_MMX
    uint8_t *cm = cropTbl + MAX_NEG_CROP;
    int sum;

    for(;size > 0;size--) {
        sum = -lum_m4[0];
        sum += lum_m3[0] << 2;
        sum += lum_m2[0] << 1;
        sum += lum_m1[0] << 2;
        sum += -lum[0];
        dst[0] = cm[(sum + 4) >> 3];
        lum_m4++;
        lum_m3++;
        lum_m2++;
        lum_m1++;
        lum++;
        dst++;
    }
#else

    {
        mmx_t rounder;
        rounder.uw[0]=4;
        rounder.uw[1]=4;
        rounder.uw[2]=4;
        rounder.uw[3]=4;
        pxor_r2r(mm7,mm7);
        movq_m2r(rounder,mm6);
    }
    for (;size > 3; size-=4) {
        DEINT_LINE_LUM
        lum_m4+=4;
        lum_m3+=4;
        lum_m2+=4;
        lum_m1+=4;
        lum+=4;
        dst+=4;
    }
#endif
}
static void deinterlace_line_inplace(uint8_t *lum_m4, uint8_t *lum_m3, uint8_t *lum_m2, uint8_t *lum_m1, uint8_t *lum,
                             int size)
{
#ifndef HAVE_MMX
    uint8_t *cm = cropTbl + MAX_NEG_CROP;
    int sum;

    for(;size > 0;size--) {
        sum = -lum_m4[0];
        sum += lum_m3[0] << 2;
        sum += lum_m2[0] << 1;
        lum_m4[0]=lum_m2[0];