| /* |
| * XBM image format |
| * |
| * Copyright (c) 2012 Paul B Mahol |
| * |
| * 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 "libavutil/reverse.h" |
| |
| #include "avcodec.h" |
| #include "codec_internal.h" |
| #include "decode.h" |
| |
| static int get_nibble(uint8_t x) |
| { |
| #define TIMES256(idx) \ |
| TIMES64(4 * (idx)) TIMES64(4 * (idx) + 1) TIMES64(4 * (idx) + 2) TIMES64(4 * (idx) + 3) |
| #define TIMES64(idx) \ |
| TIMES16(4 * (idx)) TIMES16(4 * (idx) + 1) TIMES16(4 * (idx) + 2) TIMES16(4 * (idx) + 3) |
| #define TIMES16(idx) \ |
| TIMES4(4 * (idx)) TIMES4(4 * (idx) + 1) TIMES4(4 * (idx) + 2) TIMES4(4 * (idx) + 3) |
| #define TIMES4(idx) \ |
| ENTRY(4 * (idx)) ENTRY(4 * (idx) + 1) ENTRY(4 * (idx) + 2) ENTRY(4 * (idx) + 3) |
| #define ENTRY(x) [x] = ((x) >= 'a' && (x) <= 'f') ? (x) - ('a' - 10) : \ |
| ((x) >= 'A' && (x) <= 'F') ? (x) - ('A' - 10) : \ |
| ((x) >= '0' && (x) <= '9') ? (x) - '0' : 255, |
| |
| static const uint8_t lut[] = { |
| TIMES256(0) |
| }; |
| return lut[x]; |
| } |
| |
| static int parse_str_int(const uint8_t *p, const uint8_t *end, const uint8_t *key) |
| { |
| int keylen = strlen(key); |
| const uint8_t *e = end - keylen; |
| |
| for(; p < e; p++) { |
| if (!memcmp(p, key, keylen)) |
| break; |
| } |
| p += keylen; |
| if (p >= end) |
| return INT_MIN; |
| |
| for(; p<end; p++) { |
| char *eptr; |
| int64_t ret = strtol(p, &eptr, 10); |
| if ((const uint8_t *)eptr != p) |
| return ret; |
| } |
| return INT_MIN; |
| } |
| |
| static int xbm_decode_frame(AVCodecContext *avctx, AVFrame *p, |
| int *got_frame, AVPacket *avpkt) |
| { |
| int ret, linesize, i, j; |
| int width = 0; |
| int height = 0; |
| const uint8_t *end, *ptr = avpkt->data; |
| const uint8_t *next; |
| uint8_t *dst; |
| |
| avctx->pix_fmt = AV_PIX_FMT_MONOWHITE; |
| end = avpkt->data + avpkt->size; |
| |
| width = parse_str_int(avpkt->data, end, "_width"); |
| height = parse_str_int(avpkt->data, end, "_height"); |
| |
| if ((ret = ff_set_dimensions(avctx, width, height)) < 0) |
| return ret; |
| |
| if (avctx->skip_frame >= AVDISCARD_ALL) |
| return avpkt->size; |
| |
| if ((ret = ff_get_buffer(avctx, p, 0)) < 0) |
| return ret; |
| |
| // goto start of image data |
| next = memchr(ptr, '{', avpkt->size); |
| if (!next) |
| next = memchr(ptr, '(', avpkt->size); |
| if (!next) |
| return AVERROR_INVALIDDATA; |
| ptr = next + 1; |
| |
| linesize = (avctx->width + 7) / 8; |
| for (i = 0; i < avctx->height; i++) { |
| dst = p->data[0] + i * p->linesize[0]; |
| for (j = 0; j < linesize; j++) { |
| uint8_t nib, val; |
| |
| while (ptr < end && *ptr != 'x' && *ptr != '$') |
| ptr++; |
| |
| ptr ++; |
| if (ptr < end && (val = get_nibble(*ptr)) <= 15) { |
| ptr++; |
| if ((nib = get_nibble(*ptr)) <= 15) { |
| val = (val << 4) + nib; |
| ptr++; |
| } |
| *dst++ = ff_reverse[val]; |
| if ((val = get_nibble(*ptr)) <= 15 && j+1 < linesize) { |
| j++; |
| ptr++; |
| if ((nib = get_nibble(*ptr)) <= 15) { |
| val = (val << 4) + nib; |
| ptr++; |
| } |
| *dst++ = ff_reverse[val]; |
| } |
| } else { |
| av_log(avctx, AV_LOG_ERROR, |
| "Unexpected data at %.8s.\n", ptr); |
| return AVERROR_INVALIDDATA; |
| } |
| } |
| } |
| |
| p->flags |= AV_FRAME_FLAG_KEY; |
| p->pict_type = AV_PICTURE_TYPE_I; |
| |
| *got_frame = 1; |
| |
| return avpkt->size; |
| } |
| |
| const FFCodec ff_xbm_decoder = { |
| .p.name = "xbm", |
| CODEC_LONG_NAME("XBM (X BitMap) image"), |
| .p.type = AVMEDIA_TYPE_VIDEO, |
| .p.id = AV_CODEC_ID_XBM, |
| .p.capabilities = AV_CODEC_CAP_DR1, |
| .caps_internal = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM, |
| FF_CODEC_DECODE_CB(xbm_decode_frame), |
| }; |