Libav 0.7.1
libavutil/imgutils.c
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00001 /*
00002  * This file is part of Libav.
00003  *
00004  * Libav is free software; you can redistribute it and/or
00005  * modify it under the terms of the GNU Lesser General Public
00006  * License as published by the Free Software Foundation; either
00007  * version 2.1 of the License, or (at your option) any later version.
00008  *
00009  * Libav is distributed in the hope that it will be useful,
00010  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00011  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012  * Lesser General Public License for more details.
00013  *
00014  * You should have received a copy of the GNU Lesser General Public
00015  * License along with Libav; if not, write to the Free Software
00016  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00017  */
00018 
00024 #include "imgutils.h"
00025 #include "internal.h"
00026 #include "pixdesc.h"
00027 
00028 void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
00029                                 const AVPixFmtDescriptor *pixdesc)
00030 {
00031     int i;
00032     memset(max_pixsteps, 0, 4*sizeof(max_pixsteps[0]));
00033     if (max_pixstep_comps)
00034         memset(max_pixstep_comps, 0, 4*sizeof(max_pixstep_comps[0]));
00035 
00036     for (i = 0; i < 4; i++) {
00037         const AVComponentDescriptor *comp = &(pixdesc->comp[i]);
00038         if ((comp->step_minus1+1) > max_pixsteps[comp->plane]) {
00039             max_pixsteps[comp->plane] = comp->step_minus1+1;
00040             if (max_pixstep_comps)
00041                 max_pixstep_comps[comp->plane] = i;
00042         }
00043     }
00044 }
00045 
00046 int av_image_get_linesize(enum PixelFormat pix_fmt, int width, int plane)
00047 {
00048     const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[pix_fmt];
00049     int max_step     [4];       /* max pixel step for each plane */
00050     int max_step_comp[4];       /* the component for each plane which has the max pixel step */
00051     int s;
00052 
00053     if (desc->flags & PIX_FMT_BITSTREAM)
00054         return (width * (desc->comp[0].step_minus1+1) + 7) >> 3;
00055 
00056     av_image_fill_max_pixsteps(max_step, max_step_comp, desc);
00057     s = (max_step_comp[plane] == 1 || max_step_comp[plane] == 2) ? desc->log2_chroma_w : 0;
00058     return max_step[plane] * (((width + (1 << s) - 1)) >> s);
00059 }
00060 
00061 int av_image_fill_linesizes(int linesizes[4], enum PixelFormat pix_fmt, int width)
00062 {
00063     int i;
00064     const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[pix_fmt];
00065     int max_step     [4];       /* max pixel step for each plane */
00066     int max_step_comp[4];       /* the component for each plane which has the max pixel step */
00067 
00068     memset(linesizes, 0, 4*sizeof(linesizes[0]));
00069 
00070     if ((unsigned)pix_fmt >= PIX_FMT_NB || desc->flags & PIX_FMT_HWACCEL)
00071         return AVERROR(EINVAL);
00072 
00073     if (desc->flags & PIX_FMT_BITSTREAM) {
00074         if (width > (INT_MAX -7) / (desc->comp[0].step_minus1+1))
00075             return AVERROR(EINVAL);
00076         linesizes[0] = (width * (desc->comp[0].step_minus1+1) + 7) >> 3;
00077         return 0;
00078     }
00079 
00080     av_image_fill_max_pixsteps(max_step, max_step_comp, desc);
00081     for (i = 0; i < 4; i++) {
00082         int s = (max_step_comp[i] == 1 || max_step_comp[i] == 2) ? desc->log2_chroma_w : 0;
00083         int shifted_w = ((width + (1 << s) - 1)) >> s;
00084         if (max_step[i] > INT_MAX / shifted_w)
00085             return AVERROR(EINVAL);
00086         linesizes[i] = max_step[i] * shifted_w;
00087     }
00088 
00089     return 0;
00090 }
00091 
00092 int av_image_fill_pointers(uint8_t *data[4], enum PixelFormat pix_fmt, int height,
00093                            uint8_t *ptr, const int linesizes[4])
00094 {
00095     int i, total_size, size[4], has_plane[4];
00096 
00097     const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[pix_fmt];
00098     memset(data     , 0, sizeof(data[0])*4);
00099     memset(size     , 0, sizeof(size));
00100     memset(has_plane, 0, sizeof(has_plane));
00101 
00102     if ((unsigned)pix_fmt >= PIX_FMT_NB || desc->flags & PIX_FMT_HWACCEL)
00103         return AVERROR(EINVAL);
00104 
00105     data[0] = ptr;
00106     if (linesizes[0] > (INT_MAX - 1024) / height)
00107         return AVERROR(EINVAL);
00108     size[0] = linesizes[0] * height;
00109 
00110     if (desc->flags & PIX_FMT_PAL) {
00111         size[0] = (size[0] + 3) & ~3;
00112         data[1] = ptr + size[0]; /* palette is stored here as 256 32 bits words */
00113         return size[0] + 256 * 4;
00114     }
00115 
00116     for (i = 0; i < 4; i++)
00117         has_plane[desc->comp[i].plane] = 1;
00118 
00119     total_size = size[0];
00120     for (i = 1; has_plane[i] && i < 4; i++) {
00121         int h, s = (i == 1 || i == 2) ? desc->log2_chroma_h : 0;
00122         data[i] = data[i-1] + size[i-1];
00123         h = (height + (1 << s) - 1) >> s;
00124         if (linesizes[i] > INT_MAX / h)
00125             return AVERROR(EINVAL);
00126         size[i] = h * linesizes[i];
00127         if (total_size > INT_MAX - size[i])
00128             return AVERROR(EINVAL);
00129         total_size += size[i];
00130     }
00131 
00132     return total_size;
00133 }
00134 
00135 int ff_set_systematic_pal2(uint32_t pal[256], enum PixelFormat pix_fmt)
00136 {
00137     int i;
00138 
00139     for (i = 0; i < 256; i++) {
00140         int r, g, b;
00141 
00142         switch (pix_fmt) {
00143         case PIX_FMT_RGB8:
00144             r = (i>>5    )*36;
00145             g = ((i>>2)&7)*36;
00146             b = (i&3     )*85;
00147             break;
00148         case PIX_FMT_BGR8:
00149             b = (i>>6    )*85;
00150             g = ((i>>3)&7)*36;
00151             r = (i&7     )*36;
00152             break;
00153         case PIX_FMT_RGB4_BYTE:
00154             r = (i>>3    )*255;
00155             g = ((i>>1)&3)*85;
00156             b = (i&1     )*255;
00157             break;
00158         case PIX_FMT_BGR4_BYTE:
00159             b = (i>>3    )*255;
00160             g = ((i>>1)&3)*85;
00161             r = (i&1     )*255;
00162             break;
00163         case PIX_FMT_GRAY8:
00164             r = b = g = i;
00165             break;
00166         default:
00167             return AVERROR(EINVAL);
00168         }
00169         pal[i] = b + (g<<8) + (r<<16);
00170     }
00171 
00172     return 0;
00173 }
00174 
00175 int av_image_alloc(uint8_t *pointers[4], int linesizes[4],
00176                    int w, int h, enum PixelFormat pix_fmt, int align)
00177 {
00178     int i, ret;
00179     uint8_t *buf;
00180 
00181     if ((ret = av_image_check_size(w, h, 0, NULL)) < 0)
00182         return ret;
00183     if ((ret = av_image_fill_linesizes(linesizes, pix_fmt, w)) < 0)
00184         return ret;
00185 
00186     for (i = 0; i < 4; i++)
00187         linesizes[i] = FFALIGN(linesizes[i], align);
00188 
00189     if ((ret = av_image_fill_pointers(pointers, pix_fmt, h, NULL, linesizes)) < 0)
00190         return ret;
00191     buf = av_malloc(ret + align);
00192     if (!buf)
00193         return AVERROR(ENOMEM);
00194     if ((ret = av_image_fill_pointers(pointers, pix_fmt, h, buf, linesizes)) < 0) {
00195         av_free(buf);
00196         return ret;
00197     }
00198     if (av_pix_fmt_descriptors[pix_fmt].flags & PIX_FMT_PAL)
00199         ff_set_systematic_pal2((uint32_t*)pointers[1], pix_fmt);
00200 
00201     return ret;
00202 }
00203 
00204 typedef struct ImgUtils {
00205     const AVClass *class;
00206     int   log_offset;
00207     void *log_ctx;
00208 } ImgUtils;
00209 
00210 static const AVClass imgutils_class = { "IMGUTILS", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(ImgUtils, log_offset), offsetof(ImgUtils, log_ctx) };
00211 
00212 int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
00213 {
00214     ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };
00215 
00216     if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
00217         return 0;
00218 
00219     av_log(&imgutils, AV_LOG_ERROR, "Picture size %ux%u is invalid\n", w, h);
00220     return AVERROR(EINVAL);
00221 }
00222 
00223 void av_image_copy_plane(uint8_t       *dst, int dst_linesize,
00224                          const uint8_t *src, int src_linesize,
00225                          int bytewidth, int height)
00226 {
00227     if (!dst || !src)
00228         return;
00229     for (;height > 0; height--) {
00230         memcpy(dst, src, bytewidth);
00231         dst += dst_linesize;
00232         src += src_linesize;
00233     }
00234 }
00235 
00236 void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4],
00237                    const uint8_t *src_data[4], const int src_linesizes[4],
00238                    enum PixelFormat pix_fmt, int width, int height)
00239 {
00240     const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[pix_fmt];
00241 
00242     if (desc->flags & PIX_FMT_HWACCEL)
00243         return;
00244 
00245     if (desc->flags & PIX_FMT_PAL) {
00246         av_image_copy_plane(dst_data[0], dst_linesizes[0],
00247                             src_data[0], src_linesizes[0],
00248                             width, height);
00249         /* copy the palette */
00250         memcpy(dst_data[1], src_data[1], 4*256);
00251     } else {
00252         int i, planes_nb = 0;
00253 
00254         for (i = 0; i < desc->nb_components; i++)
00255             planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
00256 
00257         for (i = 0; i < planes_nb; i++) {
00258             int h = height;
00259             int bwidth = av_image_get_linesize(pix_fmt, width, i);
00260             if (i == 1 || i == 2) {
00261                 h= -((-height)>>desc->log2_chroma_h);
00262             }
00263             av_image_copy_plane(dst_data[i], dst_linesizes[i],
00264                                 src_data[i], src_linesizes[i],
00265                                 bwidth, h);
00266         }
00267     }
00268 }