FFmpeg: libavcodec/pnmdec.c Source File

00001 /*
00002  * PNM image format
00003  * Copyright (c) 2002, 2003 Fabrice Bellard
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "avcodec.h"
00023 #include "bytestream.h"
00024 #include "put_bits.h"
00025 #include "pnm.h"
00026 
00027 
00028 static int pnm_decode_frame(AVCodecContext *avctx, void *data,
00029                             int *data_size, AVPacket *avpkt)
00030 {
00031     const uint8_t *buf   = avpkt->data;
00032     int buf_size         = avpkt->size;
00033     PNMContext * const s = avctx->priv_data;
00034     AVFrame *picture     = data;
00035     AVFrame * const p    = (AVFrame*)&s->picture;
00036     int i, j, n, linesize, h, upgrade = 0, is_mono = 0;
00037     unsigned char *ptr;
00038     int components, sample_len;
00039 
00040     s->bytestream_start =
00041     s->bytestream       = buf;
00042     s->bytestream_end   = buf + buf_size;
00043 
00044     if (ff_pnm_decode_header(avctx, s) < 0)
00045         return -1;
00046 
00047     if (p->data[0])
00048         avctx->release_buffer(avctx, p);
00049 
00050     p->reference = 0;
00051     if (avctx->get_buffer(avctx, p) < 0) {
00052         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00053         return -1;
00054     }
00055     p->pict_type = AV_PICTURE_TYPE_I;
00056     p->key_frame = 1;
00057 
00058     switch (avctx->pix_fmt) {
00059     default:
00060         return -1;
00061     case PIX_FMT_RGB48BE:
00062         n = avctx->width * 6;
00063         components=3;
00064         sample_len=16;
00065         goto do_read;
00066     case PIX_FMT_RGB24:
00067         n = avctx->width * 3;
00068         components=3;
00069         sample_len=8;
00070         goto do_read;
00071     case PIX_FMT_GRAY8:
00072         n = avctx->width;
00073         components=1;
00074         sample_len=8;
00075         if (s->maxval < 255)
00076             upgrade = 1;
00077         goto do_read;
00078     case PIX_FMT_GRAY16BE:
00079     case PIX_FMT_GRAY16LE:
00080         n = avctx->width * 2;
00081         components=1;
00082         sample_len=16;
00083         if (s->maxval < 65535)
00084             upgrade = 2;
00085         goto do_read;
00086     case PIX_FMT_MONOWHITE:
00087     case PIX_FMT_MONOBLACK:
00088         n = (avctx->width + 7) >> 3;
00089         components=1;
00090         sample_len=1;
00091         is_mono = 1;
00092     do_read:
00093         ptr      = p->data[0];
00094         linesize = p->linesize[0];
00095         if (s->bytestream + n * avctx->height > s->bytestream_end)
00096             return -1;
00097         if(s->type < 4){
00098             for (i=0; i<avctx->height; i++) {
00099                 PutBitContext pb;
00100                 init_put_bits(&pb, ptr, linesize);
00101                 for(j=0; j<avctx->width * components; j++){
00102                     unsigned int c=0;
00103                     int v=0;
00104                     while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
00105                         s->bytestream++;
00106                     if(s->bytestream >= s->bytestream_end)
00107                         return -1;
00108                     if (is_mono) {
00109                         /* read a single digit */
00110                         v = (*s->bytestream++) - '0';
00111                     } else {
00112                         /* read a sequence of digits */
00113                         do {
00114                             v = 10*v + c;
00115                             c = (*s->bytestream++) - '0';
00116                         } while (c <= 9);
00117                     }
00118                     put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);
00119                 }
00120                 flush_put_bits(&pb);
00121                 ptr+= linesize;
00122             }
00123         }else{
00124         for (i = 0; i < avctx->height; i++) {
00125             if (!upgrade)
00126                 memcpy(ptr, s->bytestream, n);
00127             else if (upgrade == 1) {
00128                 unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;
00129                 for (j = 0; j < n; j++)
00130                     ptr[j] = (s->bytestream[j] * f + 64) >> 7;
00131             } else if (upgrade == 2) {
00132                 unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;
00133                 for (j = 0; j < n / 2; j++) {
00134                     v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
00135                     ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
00136                 }
00137             }
00138             s->bytestream += n;
00139             ptr           += linesize;
00140         }
00141         }
00142         break;
00143     case PIX_FMT_YUV420P:
00144         {
00145             unsigned char *ptr1, *ptr2;
00146 
00147             n        = avctx->width;
00148             ptr      = p->data[0];
00149             linesize = p->linesize[0];
00150             if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)
00151                 return -1;
00152             for (i = 0; i < avctx->height; i++) {
00153                 memcpy(ptr, s->bytestream, n);
00154                 s->bytestream += n;
00155                 ptr           += linesize;
00156             }
00157             ptr1 = p->data[1];
00158             ptr2 = p->data[2];
00159             n >>= 1;
00160             h = avctx->height >> 1;
00161             for (i = 0; i < h; i++) {
00162                 memcpy(ptr1, s->bytestream, n);
00163                 s->bytestream += n;
00164                 memcpy(ptr2, s->bytestream, n);
00165                 s->bytestream += n;
00166                 ptr1 += p->linesize[1];
00167                 ptr2 += p->linesize[2];
00168             }
00169         }
00170         break;
00171     case PIX_FMT_RGB32:
00172         ptr      = p->data[0];
00173         linesize = p->linesize[0];
00174         if (s->bytestream + avctx->width * avctx->height * 4 > s->bytestream_end)
00175             return -1;
00176         for (i = 0; i < avctx->height; i++) {
00177             int j, r, g, b, a;
00178 
00179             for (j = 0; j < avctx->width; j++) {
00180                 r = *s->bytestream++;
00181                 g = *s->bytestream++;
00182                 b = *s->bytestream++;
00183                 a = *s->bytestream++;
00184                 ((uint32_t *)ptr)[j] = (a << 24) | (r << 16) | (g << 8) | b;
00185             }
00186             ptr += linesize;
00187         }
00188         break;
00189     }
00190     *picture   = *(AVFrame*)&s->picture;
00191     *data_size = sizeof(AVPicture);
00192 
00193     return s->bytestream - s->bytestream_start;
00194 }
00195 
00196 
00197 #if CONFIG_PGM_DECODER
00198 AVCodec ff_pgm_decoder = {
00199     "pgm",
00200     AVMEDIA_TYPE_VIDEO,
00201     CODEC_ID_PGM,
00202     sizeof(PNMContext),
00203     ff_pnm_init,
00204     NULL,
00205     ff_pnm_end,
00206     pnm_decode_frame,
00207     CODEC_CAP_DR1,
00208     .pix_fmts  = (const enum PixelFormat[]){PIX_FMT_GRAY8, PIX_FMT_GRAY16BE, PIX_FMT_NONE},
00209     .long_name = NULL_IF_CONFIG_SMALL("PGM (Portable GrayMap) image"),
00210 };
00211 #endif
00212 
00213 #if CONFIG_PGMYUV_DECODER
00214 AVCodec ff_pgmyuv_decoder = {
00215     "pgmyuv",
00216     AVMEDIA_TYPE_VIDEO,
00217     CODEC_ID_PGMYUV,
00218     sizeof(PNMContext),
00219     ff_pnm_init,
00220     NULL,
00221     ff_pnm_end,
00222     pnm_decode_frame,
00223     CODEC_CAP_DR1,
00224     .pix_fmts  = (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_NONE},
00225     .long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),
00226 };
00227 #endif
00228 
00229 #if CONFIG_PPM_DECODER
00230 AVCodec ff_ppm_decoder = {
00231     "ppm",
00232     AVMEDIA_TYPE_VIDEO,
00233     CODEC_ID_PPM,
00234     sizeof(PNMContext),
00235     ff_pnm_init,
00236     NULL,
00237     ff_pnm_end,
00238     pnm_decode_frame,
00239     CODEC_CAP_DR1,
00240     .pix_fmts  = (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB48BE, PIX_FMT_NONE},
00241     .long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),
00242 };
00243 #endif
00244 
00245 #if CONFIG_PBM_DECODER
00246 AVCodec ff_pbm_decoder = {
00247     "pbm",
00248     AVMEDIA_TYPE_VIDEO,
00249     CODEC_ID_PBM,
00250     sizeof(PNMContext),
00251     ff_pnm_init,
00252     NULL,
00253     ff_pnm_end,
00254     pnm_decode_frame,
00255     CODEC_CAP_DR1,
00256     .pix_fmts  = (const enum PixelFormat[]){PIX_FMT_MONOWHITE, PIX_FMT_NONE},
00257     .long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),
00258 };
00259 #endif
00260 
00261 #if CONFIG_PAM_DECODER
00262 AVCodec ff_pam_decoder = {
00263     "pam",
00264     AVMEDIA_TYPE_VIDEO,
00265     CODEC_ID_PAM,
00266     sizeof(PNMContext),
00267     ff_pnm_init,
00268     NULL,
00269     ff_pnm_end,
00270     pnm_decode_frame,
00271     CODEC_CAP_DR1,
00272     .pix_fmts  = (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB32, PIX_FMT_GRAY8, PIX_FMT_MONOWHITE, PIX_FMT_NONE},
00273     .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
00274 };
00275 #endif