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Diffstat (limited to 'ffmpeg/libavcodec/pcx.c')
-rw-r--r--ffmpeg/libavcodec/pcx.c234
1 files changed, 234 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/pcx.c b/ffmpeg/libavcodec/pcx.c
new file mode 100644
index 0000000..ba92332
--- /dev/null
+++ b/ffmpeg/libavcodec/pcx.c
@@ -0,0 +1,234 @@
+/*
+ * 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"
+
+static void pcx_rle_decode(GetByteContext *gb, uint8_t *dst,
+ unsigned int bytes_per_scanline, int compressed)
+{
+ unsigned int i = 0;
+ unsigned char run, value;
+
+ if (compressed) {
+ while (i<bytes_per_scanline) {
+ run = 1;
+ value = bytestream2_get_byte(gb);
+ if (value >= 0xc0) {
+ 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);
+ }
+}
+
+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, 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 < 128)
+ 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) {
+ 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 = av_image_check_size(w, h, 0, avctx)) < 0)
+ return ret;
+ if (w != avctx->width || h != avctx->height)
+ avcodec_set_dimensions(avctx, w, h);
+ 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 + FF_INPUT_BUFFER_PADDING_SIZE);
+ if (!scanline)
+ return AVERROR(ENOMEM);
+
+ if (nplanes == 3 && bits_per_pixel == 8) {
+ for (y=0; y<h; y++) {
+ pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
+
+ 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;
+
+ for (y=0; y<h; y++, ptr+=stride) {
+ pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
+ 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 = AVERROR_INVALIDDATA;
+ 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);
+
+ pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
+
+ 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++) {
+ pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
+
+ 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",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_PCX,
+ .decode = pcx_decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
+};
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