yading@10: /*
yading@10:  * PC Paintbrush PCX (.pcx) image decoder
yading@10:  * Copyright (c) 2007, 2008 Ivo van Poorten
yading@10:  *
yading@10:  * This decoder does not support CGA palettes. I am unable to find samples
yading@10:  * and Netpbm cannot generate them.
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include "libavutil/imgutils.h"
yading@10: #include "avcodec.h"
yading@10: #include "bytestream.h"
yading@10: #include "get_bits.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: static void pcx_rle_decode(GetByteContext *gb, uint8_t *dst,
yading@10:                            unsigned int bytes_per_scanline, int compressed)
yading@10: {
yading@10:     unsigned int i = 0;
yading@10:     unsigned char run, value;
yading@10: 
yading@10:     if (compressed) {
yading@10:         while (i<bytes_per_scanline) {
yading@10:             run = 1;
yading@10:             value = bytestream2_get_byte(gb);
yading@10:             if (value >= 0xc0) {
yading@10:                 run = value & 0x3f;
yading@10:                 value = bytestream2_get_byte(gb);
yading@10:             }
yading@10:             while (i<bytes_per_scanline && run--)
yading@10:                 dst[i++] = value;
yading@10:         }
yading@10:     } else {
yading@10:         bytestream2_get_buffer(gb, dst, bytes_per_scanline);
yading@10:     }
yading@10: }
yading@10: 
yading@10: static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
yading@10: {
yading@10:     int i;
yading@10: 
yading@10:     pallen = FFMIN(pallen, bytestream2_get_bytes_left(gb) / 3);
yading@10:     for (i=0; i<pallen; i++)
yading@10:         *dst++ = 0xFF000000 | bytestream2_get_be24u(gb);
yading@10:     if (pallen < 256)
yading@10:         memset(dst, 0, (256 - pallen) * sizeof(*dst));
yading@10: }
yading@10: 
yading@10: static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
yading@10:                             AVPacket *avpkt) {
yading@10:     GetByteContext gb;
yading@10:     AVFrame * const p = data;
yading@10:     int compressed, xmin, ymin, xmax, ymax, ret;
yading@10:     unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
yading@10:                  bytes_per_scanline;
yading@10:     uint8_t *ptr, *scanline;
yading@10: 
yading@10:     if (avpkt->size < 128)
yading@10:         return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     bytestream2_init(&gb, avpkt->data, avpkt->size);
yading@10: 
yading@10:     if (bytestream2_get_byteu(&gb) != 0x0a || bytestream2_get_byteu(&gb) > 5) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     compressed = bytestream2_get_byteu(&gb);
yading@10:     bits_per_pixel = bytestream2_get_byteu(&gb);
yading@10:     xmin = bytestream2_get_le16u(&gb);
yading@10:     ymin = bytestream2_get_le16u(&gb);
yading@10:     xmax = bytestream2_get_le16u(&gb);
yading@10:     ymax = bytestream2_get_le16u(&gb);
yading@10:     avctx->sample_aspect_ratio.num = bytestream2_get_le16u(&gb);
yading@10:     avctx->sample_aspect_ratio.den = bytestream2_get_le16u(&gb);
yading@10: 
yading@10:     if (xmax < xmin || ymax < ymin) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     w = xmax - xmin + 1;
yading@10:     h = ymax - ymin + 1;
yading@10: 
yading@10:     bytestream2_skipu(&gb, 49);
yading@10:     nplanes            = bytestream2_get_byteu(&gb);
yading@10:     bytes_per_line     = bytestream2_get_le16u(&gb);
yading@10:     bytes_per_scanline = nplanes * bytes_per_line;
yading@10: 
yading@10:     if (bytes_per_scanline < (w * bits_per_pixel * nplanes + 7) / 8) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     switch ((nplanes<<8) + bits_per_pixel) {
yading@10:         case 0x0308:
yading@10:             avctx->pix_fmt = AV_PIX_FMT_RGB24;
yading@10:             break;
yading@10:         case 0x0108:
yading@10:         case 0x0104:
yading@10:         case 0x0102:
yading@10:         case 0x0101:
yading@10:         case 0x0401:
yading@10:         case 0x0301:
yading@10:         case 0x0201:
yading@10:             avctx->pix_fmt = AV_PIX_FMT_PAL8;
yading@10:             break;
yading@10:         default:
yading@10:             av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
yading@10:             return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     bytestream2_skipu(&gb, 60);
yading@10: 
yading@10:     if ((ret = av_image_check_size(w, h, 0, avctx)) < 0)
yading@10:         return ret;
yading@10:     if (w != avctx->width || h != avctx->height)
yading@10:         avcodec_set_dimensions(avctx, w, h);
yading@10:     if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     p->pict_type = AV_PICTURE_TYPE_I;
yading@10: 
yading@10:     ptr    = p->data[0];
yading@10:     stride = p->linesize[0];
yading@10: 
yading@10:     scanline = av_malloc(bytes_per_scanline + FF_INPUT_BUFFER_PADDING_SIZE);
yading@10:     if (!scanline)
yading@10:         return AVERROR(ENOMEM);
yading@10: 
yading@10:     if (nplanes == 3 && bits_per_pixel == 8) {
yading@10:         for (y=0; y<h; y++) {
yading@10:             pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
yading@10: 
yading@10:             for (x=0; x<w; x++) {
yading@10:                 ptr[3*x  ] = scanline[x                    ];
yading@10:                 ptr[3*x+1] = scanline[x+ bytes_per_line    ];
yading@10:                 ptr[3*x+2] = scanline[x+(bytes_per_line<<1)];
yading@10:             }
yading@10: 
yading@10:             ptr += stride;
yading@10:         }
yading@10: 
yading@10:     } else if (nplanes == 1 && bits_per_pixel == 8) {
yading@10:         int palstart = avpkt->size - 769;
yading@10: 
yading@10:         for (y=0; y<h; y++, ptr+=stride) {
yading@10:             pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
yading@10:             memcpy(ptr, scanline, w);
yading@10:         }
yading@10: 
yading@10:         if (bytestream2_tell(&gb) != palstart) {
yading@10:             av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
yading@10:             bytestream2_seek(&gb, palstart, SEEK_SET);
yading@10:         }
yading@10:         if (bytestream2_get_byte(&gb) != 12) {
yading@10:             av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
yading@10:             ret = AVERROR_INVALIDDATA;
yading@10:             goto end;
yading@10:         }
yading@10: 
yading@10:     } else if (nplanes == 1) {   /* all packed formats, max. 16 colors */
yading@10:         GetBitContext s;
yading@10: 
yading@10:         for (y=0; y<h; y++) {
yading@10:             init_get_bits8(&s, scanline, bytes_per_scanline);
yading@10: 
yading@10:             pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
yading@10: 
yading@10:             for (x=0; x<w; x++)
yading@10:                 ptr[x] = get_bits(&s, bits_per_pixel);
yading@10:             ptr += stride;
yading@10:         }
yading@10: 
yading@10:     } else {    /* planar, 4, 8 or 16 colors */
yading@10:         int i;
yading@10: 
yading@10:         for (y=0; y<h; y++) {
yading@10:             pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
yading@10: 
yading@10:             for (x=0; x<w; x++) {
yading@10:                 int m = 0x80 >> (x&7), v = 0;
yading@10:                 for (i=nplanes - 1; i>=0; i--) {
yading@10:                     v <<= 1;
yading@10:                     v  += !!(scanline[i*bytes_per_line + (x>>3)] & m);
yading@10:                 }
yading@10:                 ptr[x] = v;
yading@10:             }
yading@10:             ptr += stride;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     ret = bytestream2_tell(&gb);
yading@10:     if (nplanes == 1 && bits_per_pixel == 8) {
yading@10:         pcx_palette(&gb, (uint32_t *) p->data[1], 256);
yading@10:         ret += 256 * 3;
yading@10:     } else if (bits_per_pixel * nplanes == 1) {
yading@10:         AV_WN32A(p->data[1]  , 0xFF000000);
yading@10:         AV_WN32A(p->data[1]+4, 0xFFFFFFFF);
yading@10:     } else if (bits_per_pixel < 8) {
yading@10:         bytestream2_seek(&gb, 16, SEEK_SET);
yading@10:         pcx_palette(&gb, (uint32_t *) p->data[1], 16);
yading@10:     }
yading@10: 
yading@10:     *got_frame = 1;
yading@10: 
yading@10: end:
yading@10:     av_free(scanline);
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: AVCodec ff_pcx_decoder = {
yading@10:     .name           = "pcx",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_PCX,
yading@10:     .decode         = pcx_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
yading@10: };