/libavcodec/pcx.c
http://github.com/FFmpeg/FFmpeg · C · 259 lines · 198 code · 38 blank · 23 comment · 62 complexity · 54abfe421fc5b462be4add52367b6159 MD5 · raw file
- /*
- * PC Paintbrush PCX (.pcx) image decoder
- * Copyright (c) 2007, 2008 Ivo van Poorten
- *
- * This decoder does not support CGA palettes. I am unable to find samples
- * and Netpbm cannot generate them.
- *
- * 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/imgutils.h"
- #include "avcodec.h"
- #include "bytestream.h"
- #include "get_bits.h"
- #include "internal.h"
- #define PCX_HEADER_SIZE 128
- static int pcx_rle_decode(GetByteContext *gb,
- uint8_t *dst,
- unsigned int bytes_per_scanline,
- int compressed)
- {
- unsigned int i = 0;
- unsigned char run, value;
- if (bytestream2_get_bytes_left(gb) < 1)
- return AVERROR_INVALIDDATA;
- if (compressed) {
- while (i < bytes_per_scanline && bytestream2_get_bytes_left(gb)>0) {
- run = 1;
- value = bytestream2_get_byte(gb);
- if (value >= 0xc0 && bytestream2_get_bytes_left(gb)>0) {
- run = value & 0x3f;
- value = bytestream2_get_byte(gb);
- }
- while (i < bytes_per_scanline && run--)
- dst[i++] = value;
- }
- } else {
- bytestream2_get_buffer(gb, dst, bytes_per_scanline);
- }
- return 0;
- }
- static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
- {
- int i;
- pallen = FFMIN(pallen, bytestream2_get_bytes_left(gb) / 3);
- for (i = 0; i < pallen; i++)
- *dst++ = 0xFF000000 | bytestream2_get_be24u(gb);
- if (pallen < 256)
- memset(dst, 0, (256 - pallen) * sizeof(*dst));
- }
- static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
- AVPacket *avpkt)
- {
- GetByteContext gb;
- AVFrame * const p = data;
- int compressed, xmin, ymin, xmax, ymax;
- int ret;
- unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
- bytes_per_scanline;
- uint8_t *ptr, *scanline;
- if (avpkt->size < PCX_HEADER_SIZE) {
- av_log(avctx, AV_LOG_ERROR, "Packet too small\n");
- return AVERROR_INVALIDDATA;
- }
- bytestream2_init(&gb, avpkt->data, avpkt->size);
- if (bytestream2_get_byteu(&gb) != 0x0a || bytestream2_get_byteu(&gb) > 5) {
- av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n");
- return AVERROR_INVALIDDATA;
- }
- compressed = bytestream2_get_byteu(&gb);
- bits_per_pixel = bytestream2_get_byteu(&gb);
- xmin = bytestream2_get_le16u(&gb);
- ymin = bytestream2_get_le16u(&gb);
- xmax = bytestream2_get_le16u(&gb);
- ymax = bytestream2_get_le16u(&gb);
- avctx->sample_aspect_ratio.num = bytestream2_get_le16u(&gb);
- avctx->sample_aspect_ratio.den = bytestream2_get_le16u(&gb);
- if (xmax < xmin || ymax < ymin) {
- av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
- return AVERROR_INVALIDDATA;
- }
- w = xmax - xmin + 1;
- h = ymax - ymin + 1;
- bytestream2_skipu(&gb, 49);
- nplanes = bytestream2_get_byteu(&gb);
- bytes_per_line = bytestream2_get_le16u(&gb);
- bytes_per_scanline = nplanes * bytes_per_line;
- if (bytes_per_scanline < (w * bits_per_pixel * nplanes + 7) / 8 ||
- (!compressed && bytes_per_scanline > bytestream2_get_bytes_left(&gb) / h)) {
- av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n");
- return AVERROR_INVALIDDATA;
- }
- switch ((nplanes << 8) + bits_per_pixel) {
- case 0x0308:
- avctx->pix_fmt = AV_PIX_FMT_RGB24;
- break;
- case 0x0108:
- case 0x0104:
- case 0x0102:
- case 0x0101:
- case 0x0401:
- case 0x0301:
- case 0x0201:
- avctx->pix_fmt = AV_PIX_FMT_PAL8;
- break;
- default:
- av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
- return AVERROR_INVALIDDATA;
- }
- bytestream2_skipu(&gb, 60);
- if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
- return ret;
- if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
- return ret;
- p->pict_type = AV_PICTURE_TYPE_I;
- ptr = p->data[0];
- stride = p->linesize[0];
- scanline = av_malloc(bytes_per_scanline + AV_INPUT_BUFFER_PADDING_SIZE);
- if (!scanline)
- return AVERROR(ENOMEM);
- if (nplanes == 3 && bits_per_pixel == 8) {
- for (y = 0; y < h; y++) {
- ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
- if (ret < 0)
- goto end;
- for (x = 0; x < w; x++) {
- ptr[3 * x] = scanline[x];
- ptr[3 * x + 1] = scanline[x + bytes_per_line];
- ptr[3 * x + 2] = scanline[x + (bytes_per_line << 1)];
- }
- ptr += stride;
- }
- } else if (nplanes == 1 && bits_per_pixel == 8) {
- int palstart = avpkt->size - 769;
- if (avpkt->size < 769) {
- av_log(avctx, AV_LOG_ERROR, "File is too short\n");
- ret = avctx->err_recognition & AV_EF_EXPLODE ?
- AVERROR_INVALIDDATA : avpkt->size;
- goto end;
- }
- for (y = 0; y < h; y++, ptr += stride) {
- ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
- if (ret < 0)
- goto end;
- memcpy(ptr, scanline, w);
- }
- if (bytestream2_tell(&gb) != palstart) {
- av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
- bytestream2_seek(&gb, palstart, SEEK_SET);
- }
- if (bytestream2_get_byte(&gb) != 12) {
- av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
- ret = avctx->err_recognition & AV_EF_EXPLODE ?
- AVERROR_INVALIDDATA : avpkt->size;
- goto end;
- }
- } else if (nplanes == 1) { /* all packed formats, max. 16 colors */
- GetBitContext s;
- for (y = 0; y < h; y++) {
- init_get_bits8(&s, scanline, bytes_per_scanline);
- ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
- if (ret < 0)
- goto end;
- for (x = 0; x < w; x++)
- ptr[x] = get_bits(&s, bits_per_pixel);
- ptr += stride;
- }
- } else { /* planar, 4, 8 or 16 colors */
- int i;
- for (y = 0; y < h; y++) {
- ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
- if (ret < 0)
- goto end;
- for (x = 0; x < w; x++) {
- int m = 0x80 >> (x & 7), v = 0;
- for (i = nplanes - 1; i >= 0; i--) {
- v <<= 1;
- v += !!(scanline[i * bytes_per_line + (x >> 3)] & m);
- }
- ptr[x] = v;
- }
- ptr += stride;
- }
- }
- ret = bytestream2_tell(&gb);
- if (nplanes == 1 && bits_per_pixel == 8) {
- pcx_palette(&gb, (uint32_t *)p->data[1], 256);
- ret += 256 * 3;
- } else if (bits_per_pixel * nplanes == 1) {
- AV_WN32A(p->data[1] , 0xFF000000);
- AV_WN32A(p->data[1]+4, 0xFFFFFFFF);
- } else if (bits_per_pixel < 8) {
- bytestream2_seek(&gb, 16, SEEK_SET);
- pcx_palette(&gb, (uint32_t *)p->data[1], 16);
- }
- *got_frame = 1;
- end:
- av_free(scanline);
- return ret;
- }
- AVCodec ff_pcx_decoder = {
- .name = "pcx",
- .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
- .type = AVMEDIA_TYPE_VIDEO,
- .id = AV_CODEC_ID_PCX,
- .decode = pcx_decode_frame,
- .capabilities = AV_CODEC_CAP_DR1,
- };