libavcodec/pnm.c

   1 /*
   2  * PNM image format
   3  * Copyright (c) 2002, 2003 Fabrice Bellard
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #include "libavutil/imgutils.h"
  26 #include "avcodec.h"
  27 #include "pnm.h"
  28
  29 static inline int pnm_space(int c)
  30 {
  31     return c == ' ' || c == '\n' || c == '\r' || c == '\t';
  32 }
  33
  34 static void pnm_get(PNMContext *sc, char *str, int buf_size)
  35 {
  36     char *s;
  37     int c;
  38
  39     /* skip spaces and comments */
  40     for (;;) {
  41         c = *sc->bytestream++;
  42         if (c == '#')  {
  43             do {
  44                 c = *sc->bytestream++;
  45             } while (c != '\n' && sc->bytestream < sc->bytestream_end);
  46         } else if (!pnm_space(c)) {
  47             break;
  48         }
  49     }
  50
  51     s = str;
  52     while (sc->bytestream < sc->bytestream_end && !pnm_space(c)) {
  53         if ((s - str)  < buf_size - 1)
  54             *s++ = c;
  55         c = *sc->bytestream++;
  56     }
  57     *s = '\0';
  58 }
  59
  60 int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext * const s)
  61 {
  62     char buf1[32], tuple_type[32];
  63     int h, w, depth, maxval;
  64
  65     pnm_get(s, buf1, sizeof(buf1));
  66     s->type= buf1[1]-'0';
  67     if(buf1[0] != 'P')
  68         return AVERROR_INVALIDDATA;
  69
  70     if (s->type==1 || s->type==4) {
  71         avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
  72     } else if (s->type==2 || s->type==5) {
  73         if (avctx->codec_id == AV_CODEC_ID_PGMYUV)
  74             avctx->pix_fmt = AV_PIX_FMT_YUV420P;
  75         else
  76             avctx->pix_fmt = AV_PIX_FMT_GRAY8;
  77     } else if (s->type==3 || s->type==6) {
  78         avctx->pix_fmt = AV_PIX_FMT_RGB24;
  79     } else if (s->type==7) {
  80         w      = -1;
  81         h      = -1;
  82         maxval = -1;
  83         depth  = -1;
  84         tuple_type[0] = '\0';
  85         for (;;) {
  86             pnm_get(s, buf1, sizeof(buf1));
  87             if (!strcmp(buf1, "WIDTH")) {
  88                 pnm_get(s, buf1, sizeof(buf1));
  89                 w = strtol(buf1, NULL, 10);
  90             } else if (!strcmp(buf1, "HEIGHT")) {
  91                 pnm_get(s, buf1, sizeof(buf1));
  92                 h = strtol(buf1, NULL, 10);
  93             } else if (!strcmp(buf1, "DEPTH")) {
  94                 pnm_get(s, buf1, sizeof(buf1));
  95                 depth = strtol(buf1, NULL, 10);
  96             } else if (!strcmp(buf1, "MAXVAL")) {
  97                 pnm_get(s, buf1, sizeof(buf1));
  98                 maxval = strtol(buf1, NULL, 10);
  99             } else if (!strcmp(buf1, "TUPLTYPE") ||
 100                        /* libavcodec used to write invalid files */
 101                        !strcmp(buf1, "TUPLETYPE")) {
 102                 pnm_get(s, tuple_type, sizeof(tuple_type));
 103             } else if (!strcmp(buf1, "ENDHDR")) {
 104                 break;
 105             } else {
 106                 return AVERROR_INVALIDDATA;
 107             }
 108         }
 109         /* check that all tags are present */
 110         if (w <= 0 || h <= 0 || maxval <= 0 || depth <= 0 || tuple_type[0] == '\0' || av_image_check_size(w, h, 0, avctx))
 111             return AVERROR_INVALIDDATA;
 112
 113         avctx->width  = w;
 114         avctx->height = h;
 115         if (depth == 1) {
 116             if (maxval == 1)
 117                 avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
 118             else
 119                 avctx->pix_fmt = AV_PIX_FMT_GRAY8;
 120         } else if (depth == 3) {
 121             if (maxval < 256) {
 122             avctx->pix_fmt = AV_PIX_FMT_RGB24;
 123             } else {
 124                 av_log(avctx, AV_LOG_ERROR, "16-bit components are only supported for grayscale\n");
 125                 avctx->pix_fmt = AV_PIX_FMT_NONE;
 126                 return AVERROR_INVALIDDATA;
 127             }
 128         } else if (depth == 4) {
 129             avctx->pix_fmt = AV_PIX_FMT_RGB32;
 130         } else {
 131             return AVERROR_INVALIDDATA;
 132         }
 133         return 0;
 134     } else {
 135         return AVERROR_INVALIDDATA;
 136     }
 137     pnm_get(s, buf1, sizeof(buf1));
 138     avctx->width = atoi(buf1);
 139     if (avctx->width <= 0)
 140         return AVERROR_INVALIDDATA;
 141     pnm_get(s, buf1, sizeof(buf1));
 142     avctx->height = atoi(buf1);
 143     if(av_image_check_size(avctx->width, avctx->height, 0, avctx))
 144         return AVERROR_INVALIDDATA;
 145     if (avctx->pix_fmt != AV_PIX_FMT_MONOWHITE) {
 146         pnm_get(s, buf1, sizeof(buf1));
 147         s->maxval = atoi(buf1);
 148         if (s->maxval <= 0) {
 149             av_log(avctx, AV_LOG_ERROR, "Invalid maxval: %d\n", s->maxval);
 150             s->maxval = 255;
 151         }
 152         if (s->maxval >= 256) {
 153             if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
 154                 avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
 155                 if (s->maxval != 65535)
 156                     avctx->pix_fmt = AV_PIX_FMT_GRAY16;
 157             } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
 158                 if (s->maxval > 255)
 159                     avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
 160             } else if (avctx->pix_fmt == AV_PIX_FMT_YUV420P && s->maxval < 65536) {
 161                 if (s->maxval < 512)
 162                     avctx->pix_fmt = AV_PIX_FMT_YUV420P9BE;
 163                 else if (s->maxval < 1024)
 164                     avctx->pix_fmt = AV_PIX_FMT_YUV420P10BE;
 165                 else
 166                     avctx->pix_fmt = AV_PIX_FMT_YUV420P16;
 167             } else {
 168                 av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format\n");
 169                 avctx->pix_fmt = AV_PIX_FMT_NONE;
 170                 return AVERROR_INVALIDDATA;
 171             }
 172         }
 173     }else
 174         s->maxval=1;
 175     /* more check if YUV420 */
 176     if (av_pix_fmt_desc_get(avctx->pix_fmt)->flags & AV_PIX_FMT_FLAG_PLANAR) {
 177         if ((avctx->width & 1) != 0)
 178             return AVERROR_INVALIDDATA;
 179         h = (avctx->height * 2);
 180         if ((h % 3) != 0)
 181             return AVERROR_INVALIDDATA;
 182         h /= 3;
 183         avctx->height = h;
 184     }
 185     return 0;
 186 }