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

{
    AVPicture tmpsrc = *src;
    tmpsrc.data[0]++;
    gray16_to_gray(dst, &tmpsrc, width, height);
}

static void gray16_to_gray16(AVPicture *dst, const AVPicture *src,
                              int width, int height)
{
    int x, y, src_wrap, dst_wrap;
    uint16_t *s, *d;
    s = src->data[0];
    src_wrap = (src->linesize[0] - width * 2)/2;
    d = dst->data[0];
    dst_wrap = (dst->linesize[0] - width * 2)/2;
    for(y=0; y<height; y++){
        for(x=0; x<width; x++){
            *d++ = bswap_16(*s++);
        }
        s += src_wrap;
        d += dst_wrap;
    }
}


typedef struct ConvertEntry {
    void (*convert)(AVPicture *dst,
                    const AVPicture *src, int width, int height);
} ConvertEntry;

/* Add each new conversion function in this table. In order to be able
   to convert from any format to any format, the following constraints
   must be satisfied:

   - all FF_COLOR_RGB formats must convert to and from PIX_FMT_RGB24

   - all FF_COLOR_GRAY formats must convert to and from PIX_FMT_GRAY8

   - all FF_COLOR_RGB formats with alpha must convert to and from PIX_FMT_RGB32

   - PIX_FMT_YUV444P and PIX_FMT_YUVJ444P must convert to and from
     PIX_FMT_RGB24.

   - PIX_FMT_422 must convert to and from PIX_FMT_422P.

   The other conversion functions are just optimisations for common cases.
*/
static const ConvertEntry convert_table[PIX_FMT_NB][PIX_FMT_NB] = {
    [PIX_FMT_YUV420P] = {
        [PIX_FMT_YUYV422] = {
            .convert = yuv420p_to_yuyv422,
        },
        [PIX_FMT_RGB555] = {
            .convert = yuv420p_to_rgb555
        },
        [PIX_FMT_RGB565] = {
            .convert = yuv420p_to_rgb565
        },
        [PIX_FMT_BGR24] = {
            .convert = yuv420p_to_bgr24
        },
        [PIX_FMT_RGB24] = {
            .convert = yuv420p_to_rgb24
        },
        [PIX_FMT_RGB32] = {
            .convert = yuv420p_to_rgb32
        },
        [PIX_FMT_UYVY422] = {
            .convert = yuv420p_to_uyvy422,
        },
    },
    [PIX_FMT_YUV422P] = {
        [PIX_FMT_YUYV422] = {
            .convert = yuv422p_to_yuyv422,
        },
        [PIX_FMT_UYVY422] = {
            .convert = yuv422p_to_uyvy422,
        },
    },
    [PIX_FMT_YUV444P] = {
        [PIX_FMT_RGB24] = {
            .convert = yuv444p_to_rgb24
        },
    },
    [PIX_FMT_YUVJ420P] = {
        [PIX_FMT_RGB555] = {
            .convert = yuvj420p_to_rgb555
        },
        [PIX_FMT_RGB565] = {
            .convert = yuvj420p_to_rgb565
        },
        [PIX_FMT_BGR24] = {
            .convert = yuvj420p_to_bgr24
        },
        [PIX_FMT_RGB24] = {
            .convert = yuvj420p_to_rgb24
        },
        [PIX_FMT_RGB32] = {
            .convert = yuvj420p_to_rgb32
        },
    },
    [PIX_FMT_YUVJ444P] = {
        [PIX_FMT_RGB24] = {
            .convert = yuvj444p_to_rgb24
        },
    },
    [PIX_FMT_YUYV422] = {
        [PIX_FMT_YUV420P] = {
            .convert = yuyv422_to_yuv420p,
        },
        [PIX_FMT_YUV422P] = {
            .convert = yuyv422_to_yuv422p,
        },
    },
    [PIX_FMT_UYVY422] = {
        [PIX_FMT_YUV420P] = {
            .convert = uyvy422_to_yuv420p,
        },
        [PIX_FMT_YUV422P] = {
            .convert = uyvy422_to_yuv422p,
        },
    },
    [PIX_FMT_RGB24] = {
        [PIX_FMT_YUV420P] = {
            .convert = rgb24_to_yuv420p
        },
        [PIX_FMT_RGB565] = {
            .convert = rgb24_to_rgb565
        },
        [PIX_FMT_RGB555] = {
            .convert = rgb24_to_rgb555
        },
        [PIX_FMT_RGB32] = {
            .convert = rgb24_to_rgb32
        },
        [PIX_FMT_BGR24] = {
            .convert = rgb24_to_bgr24
        },
        [PIX_FMT_GRAY8] = {
            .convert = rgb24_to_gray
        },
        [PIX_FMT_PAL8] = {
            .convert = rgb24_to_pal8
        },
        [PIX_FMT_YUV444P] = {
            .convert = rgb24_to_yuv444p
        },
        [PIX_FMT_YUVJ420P] = {
            .convert = rgb24_to_yuvj420p
        },
        [PIX_FMT_YUVJ444P] = {
            .convert = rgb24_to_yuvj444p
        },
    },
    [PIX_FMT_RGB32] = {
        [PIX_FMT_RGB24] = {
            .convert = rgb32_to_rgb24
        },
        [PIX_FMT_BGR24] = {
            .convert = rgb32_to_bgr24
        },
        [PIX_FMT_RGB565] = {
            .convert = rgb32_to_rgb565
        },
        [PIX_FMT_RGB555] = {
            .convert = rgb32_to_rgb555
        },
        [PIX_FMT_PAL8] = {
            .convert = rgb32_to_pal8
        },
        [PIX_FMT_YUV420P] = {
            .convert = rgb32_to_yuv420p
        },
        [PIX_FMT_GRAY8] = {
            .convert = rgb32_to_gray
        },
    },
    [PIX_FMT_BGR24] = {
        [PIX_FMT_RGB32] = {
            .convert = bgr24_to_rgb32
        },
        [PIX_FMT_RGB24] = {
            .convert = bgr24_to_rgb24
        },
        [PIX_FMT_YUV420P] = {
            .convert = bgr24_to_yuv420p
        },
        [PIX_FMT_GRAY8] = {
            .convert = bgr24_to_gray
        },
    },
    [PIX_FMT_RGB555] = {
        [PIX_FMT_RGB24] = {
            .convert = rgb555_to_rgb24
        },
        [PIX_FMT_RGB32] = {
            .convert = rgb555_to_rgb32
        },
        [PIX_FMT_YUV420P] = {
            .convert = rgb555_to_yuv420p
        },
        [PIX_FMT_GRAY8] = {
            .convert = rgb555_to_gray
        },
    },
    [PIX_FMT_RGB565] = {
        [PIX_FMT_RGB32] = {
            .convert = rgb565_to_rgb32
        },
        [PIX_FMT_RGB24] = {
            .convert = rgb565_to_rgb24
        },
        [PIX_FMT_YUV420P] = {
            .convert = rgb565_to_yuv420p
        },
        [PIX_FMT_GRAY8] = {
            .convert = rgb565_to_gray
        },
    },
    [PIX_FMT_GRAY16BE] = {
        [PIX_FMT_GRAY8] = {
            .convert = gray16be_to_gray
        },
        [PIX_FMT_GRAY16LE] = {
            .convert = gray16_to_gray16
        },
    },
    [PIX_FMT_GRAY16LE] = {
        [PIX_FMT_GRAY8] = {
            .convert = gray16le_to_gray
        },
        [PIX_FMT_GRAY16BE] = {
            .convert = gray16_to_gray16
        },
    },
    [PIX_FMT_GRAY8] = {
        [PIX_FMT_RGB555] = {
            .convert = gray_to_rgb555
        },
        [PIX_FMT_RGB565] = {
            .convert = gray_to_rgb565
        },
        [PIX_FMT_RGB24] = {
            .convert = gray_to_rgb24
        },
        [PIX_FMT_BGR24] = {
            .convert = gray_to_bgr24
        },
        [PIX_FMT_RGB32] = {
            .convert = gray_to_rgb32
        },
        [PIX_FMT_MONOWHITE] = {
            .convert = gray_to_monowhite
        },
        [PIX_FMT_MONOBLACK] = {
            .convert = gray_to_monoblack
        },
        [PIX_FMT_GRAY16LE] = {
            .convert = gray_to_gray16
        },
        [PIX_FMT_GRAY16BE] = {
            .convert = gray_to_gray16
        },
    },
    [PIX_FMT_MONOWHITE] = {
        [PIX_FMT_GRAY8] = {
            .convert = monowhite_to_gray
        },
    },
    [PIX_FMT_MONOBLACK] = {
        [PIX_FMT_GRAY8] = {
            .convert = monoblack_to_gray
        },
    },
    [PIX_FMT_PAL8] = {
        [PIX_FMT_RGB555] = {
            .convert = pal8_to_rgb555
        },
        [PIX_FMT_RGB565] = {
            .convert = pal8_to_rgb565
        },
        [PIX_FMT_BGR24] = {
            .convert = pal8_to_bgr24
        },
        [PIX_FMT_RGB24] = {
            .convert = pal8_to_rgb24
        },
        [PIX_FMT_RGB32] = {
            .convert = pal8_to_rgb32
        },
    },
    [PIX_FMT_UYYVYY411] = {
        [PIX_FMT_YUV411P] = {
            .convert = uyyvyy411_to_yuv411p,
        },
    },

};

int avpicture_alloc(AVPicture *picture,
                           int pix_fmt, int width, int height)
{
    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(const PixFmtInfo *ps)
{
    return (ps->color_type == FF_COLOR_YUV ||
            ps->color_type == FF_COLOR_YUV_JPEG) &&
        ps->pixel_type == FF_PIXEL_PLANAR;
}

int av_picture_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;
}

int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width,
            int pix_fmt, int padtop, int padbottom, int padleft, int padright,
            int *color)
{
    uint8_t *optr;
    int y_shift;
    int x_shift;
    int yheight;
    int i, y;

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

    for (i = 0; i < 3; i++) {
        x_shift = i ? pix_fmt_info[pix_fmt].x_chroma_shift : 0;
        y_shift = i ? pix_fmt_info[pix_fmt].y_chroma_shift : 0;

        if (padtop || padleft) {
            memset(dst->data[i], color[i],
                dst->linesize[i] * (padtop >> y_shift) + (padleft >> x_shift));
        }

        if (padleft || padright) {
            optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
                (dst->linesize[i] - (padright >> x_shift));
            yheight = (height - 1 - (padtop + padbottom)) >> y_shift;
            for (y = 0; y < yheight; y++) {
                memset(optr, color[i], (padleft + padright) >> x_shift);
                optr += dst->linesize[i];
            }
        }

        if (src) { /* first line */
            uint8_t *iptr = src->data[i];
            optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
                    (padleft >> x_shift);
            memcpy(optr, iptr, src->linesize[i]);
            iptr += src->linesize[i];
            optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
                (dst->linesize[i] - (padright >> x_shift));
            yheight = (height - 1 - (padtop + padbottom)) >> y_shift;
            for (y = 0; y < yheight; y++) {
                memset(optr, color[i], (padleft + padright) >> x_shift);
                memcpy(optr + ((padleft + padright) >> x_shift), iptr,
                    src->linesize[i]);
                iptr += src->linesize[i];
                optr += dst->linesize[i];
            }
        }

        if (padbottom || padright) {
            optr = dst->data[i] + dst->linesize[i] *
                ((height - padbottom) >> y_shift) - (padright >> x_shift);
            memset(optr, color[i],dst->linesize[i] *
                (padbottom >> y_shift) + (padright >> x_shift));
        }
    }
    return 0;
}

#if LIBAVCODEC_VERSION_INT < ((52<<16)+(0<<8)+0)
void img_copy(AVPicture *dst, const AVPicture *src,
              int pix_fmt, int width, int height)
{
    av_picture_copy(dst, src, pix_fmt, width, height);
}

int img_crop(AVPicture *dst, const AVPicture *src,
              int pix_fmt, int top_band, int left_band)
{
    return av_picture_crop(dst, src, pix_fmt, top_band, left_band);
}

int img_pad(AVPicture *dst, const AVPicture *src, int height, int width,
            int pix_fmt, int padtop, int padbottom, int padleft, int padright,
            int *color)
{
    return av_picture_pad(dst, src, height, width, pix_fmt, padtop, padbottom, padleft, padright, color);
}
#endif

#ifndef CONFIG_SWSCALER
/* 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;
    const PixFmtInfo *src_pix, *dst_pix;
    const 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 */
        av_picture_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(