diff options
Diffstat (limited to 'libavcodec/pnm_common.c')
| -rw-r--r-- | libavcodec/pnm_common.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/libavcodec/pnm_common.c b/libavcodec/pnm_common.c new file mode 100644 index 0000000000..1f28aced69 --- /dev/null +++ b/libavcodec/pnm_common.c @@ -0,0 +1,147 @@ +/* + * PNM image format + * Copyright (c) 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 + */ +#include "avcodec.h" +#include "pnm.h" + +static inline int pnm_space(int c) +{ + return (c == ' ' || c == '\n' || c == '\r' || c == '\t'); +} + +static void pnm_get(PNMContext *sc, char *str, int buf_size) +{ + char *s; + int c; + + /* skip spaces and comments */ + for(;;) { + c = *sc->bytestream++; + if (c == '#') { + do { + c = *sc->bytestream++; + } while (c != '\n' && sc->bytestream < sc->bytestream_end); + } else if (!pnm_space(c)) { + break; + } + } + + s = str; + while (sc->bytestream < sc->bytestream_end && !pnm_space(c)) { + if ((s - str) < buf_size - 1) + *s++ = c; + c = *sc->bytestream++; + } + *s = '\0'; +} + +int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext * const s){ + char buf1[32], tuple_type[32]; + int h, w, depth, maxval; + + pnm_get(s, buf1, sizeof(buf1)); + if (!strcmp(buf1, "P4")) { + avctx->pix_fmt = PIX_FMT_MONOWHITE; + } else if (!strcmp(buf1, "P5")) { + if (avctx->codec_id == CODEC_ID_PGMYUV) + avctx->pix_fmt = PIX_FMT_YUV420P; + else + avctx->pix_fmt = PIX_FMT_GRAY8; + } else if (!strcmp(buf1, "P6")) { + avctx->pix_fmt = PIX_FMT_RGB24; + } else if (!strcmp(buf1, "P7")) { + w = -1; + h = -1; + maxval = -1; + depth = -1; + tuple_type[0] = '\0'; + for(;;) { + pnm_get(s, buf1, sizeof(buf1)); + if (!strcmp(buf1, "WIDTH")) { + pnm_get(s, buf1, sizeof(buf1)); + w = strtol(buf1, NULL, 10); + } else if (!strcmp(buf1, "HEIGHT")) { + pnm_get(s, buf1, sizeof(buf1)); + h = strtol(buf1, NULL, 10); + } else if (!strcmp(buf1, "DEPTH")) { + pnm_get(s, buf1, sizeof(buf1)); + depth = strtol(buf1, NULL, 10); + } else if (!strcmp(buf1, "MAXVAL")) { + pnm_get(s, buf1, sizeof(buf1)); + maxval = strtol(buf1, NULL, 10); + } else if (!strcmp(buf1, "TUPLETYPE")) { + pnm_get(s, tuple_type, sizeof(tuple_type)); + } else if (!strcmp(buf1, "ENDHDR")) { + break; + } else { + return -1; + } + } + /* check that all tags are present */ + if (w <= 0 || h <= 0 || maxval <= 0 || depth <= 0 || tuple_type[0] == '\0' || avcodec_check_dimensions(avctx, w, h)) + return -1; + + avctx->width = w; + avctx->height = h; + if (depth == 1) { + if (maxval == 1) + avctx->pix_fmt = PIX_FMT_MONOWHITE; + else + avctx->pix_fmt = PIX_FMT_GRAY8; + } else if (depth == 3) { + avctx->pix_fmt = PIX_FMT_RGB24; + } else if (depth == 4) { + avctx->pix_fmt = PIX_FMT_RGB32; + } else { + return -1; + } + return 0; + } else { + return -1; + } + pnm_get(s, buf1, sizeof(buf1)); + avctx->width = atoi(buf1); + if (avctx->width <= 0) + return -1; + pnm_get(s, buf1, sizeof(buf1)); + avctx->height = atoi(buf1); + if(avcodec_check_dimensions(avctx, avctx->width, avctx->height)) + return -1; + if (avctx->pix_fmt != PIX_FMT_MONOWHITE) { + pnm_get(s, buf1, sizeof(buf1)); + s->maxval = atoi(buf1); + if(s->maxval >= 256 && avctx->pix_fmt == PIX_FMT_GRAY8) { + avctx->pix_fmt = PIX_FMT_GRAY16BE; + if (s->maxval != 65535) + avctx->pix_fmt = PIX_FMT_GRAY16; + } + } + /* more check if YUV420 */ + if (avctx->pix_fmt == PIX_FMT_YUV420P) { + if ((avctx->width & 1) != 0) + return -1; + h = (avctx->height * 2); + if ((h % 3) != 0) + return -1; + h /= 3; + avctx->height = h; + } + return 0; +} |