Pictor/PC Paint decoder

Originally committed as revision 23532 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 250 insertions, 0 deletions

diff --git a/libavcodec/pictordec.c b/libavcodec/pictordec.c
new file mode 100644
index 0000000000..735ec82ca9
--- /dev/null
+++ b/libavcodec/pictordec.c
@@ -0,0 +1,250 @@
+/*
+ * Pictor/PC Paint decoder
+ * Copyright (c) 2010 Peter Ross <pross@xvid.org>
+ *
+ * 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
+ */
+
+/**
+ * @file libavcodec/picdec.c
+ * Pictor/PC Paint decoder
+ */
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "cga_data.h"
+
+typedef struct PicContext {
+    AVFrame frame;
+    int width, height;
+    int nb_planes;
+} PicContext;
+
+static void picmemset_8bpp(PicContext *s, int value, int run, int *x, int *y)
+{
+    while (run > 0) {
+        uint8_t *d = s->frame.data[0] + *y * s->frame.linesize[0];
+        if (*x + run >= s->width) {
+            int n = s->width - *x;
+            memset(d + *x, value, n);
+            run -= n;
+            *x = 0;
+            *y -= 1;
+            if (*y < 0)
+                break;
+        } else {
+            memset(d + *x, value, run);
+            *x += run;
+            break;
+        }
+    }
+}
+
+static void picmemset(PicContext *s, int value, int run, int *x, int *y, int *plane, int bits_per_plane)
+{
+    uint8_t *d;
+    int shift = *plane * bits_per_plane;
+    int mask  = ((1 << bits_per_plane) - 1) << shift;
+    value   <<= shift;
+
+    while (run > 0) {
+        int j;
+        for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
+            d = s->frame.data[0] + *y * s->frame.linesize[0];
+            d[*x] |= (value >> j) & mask;
+            *x += 1;
+            if (*x == s->width) {
+                *y -= 1;
+                *x = 0;
+                if (*y < 0) {
+                   *y = s->height - 1;
+                   *plane += 1;
+                   value <<= bits_per_plane;
+                   mask  <<= bits_per_plane;
+                   if (*plane >= s->nb_planes)
+                       break;
+                }
+            }
+        }
+        run--;
+    }
+}
+
+static const uint8_t cga_mode45_index[6][4] = {
+    [0] = { 0, 3,  5,   7 }, // mode4, palette#1, low intensity
+    [1] = { 0, 2,  4,   6 }, // mode4, palette#2, low intensity
+    [2] = { 0, 3,  4,   7 }, // mode5, low intensity
+    [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity
+    [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity
+    [5] = { 0, 11, 12, 15 }, // mode5, high intensity
+};
+
+static int decode_frame(AVCodecContext *avctx,
+                        void *data, int *data_size,
+                        AVPacket *avpkt)
+{
+    PicContext *s = avctx->priv_data;
+    int buf_size = avpkt->size;
+    const uint8_t *buf = avpkt->data;
+    const uint8_t *buf_end = avpkt->data + buf_size;
+    uint32_t *palette;
+    int bits_per_plane, bpp, etype, esize, npal;
+    int i, x, y, plane;
+
+    if (buf_size < 11)
+        return AVERROR_INVALIDDATA;
+
+    if (bytestream_get_le16(&buf) != 0x1234)
+        return AVERROR_INVALIDDATA;
+    s->width  = bytestream_get_le16(&buf);
+    s->height = bytestream_get_le16(&buf);
+    buf += 4;
+    bits_per_plane    = *buf & 0xF;
+    s->nb_planes      = (*buf++ >> 4) + 1;
+    bpp               = s->nb_planes ? bits_per_plane*s->nb_planes : bits_per_plane;
+    if (bits_per_plane > 8 || bpp < 1 || bpp > 32) {
+        av_log_ask_for_sample(s, "unsupported bit depth\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (*buf == 0xFF) {
+        buf += 2;
+        etype  = bytestream_get_le16(&buf);
+        esize  = bytestream_get_le16(&buf);
+        if (buf_end - buf < esize)
+            return AVERROR_INVALIDDATA;
+    } else {
+        etype = -1;
+        esize = 0;
+    }
+
+    avctx->pix_fmt = PIX_FMT_PAL8;
+
+    if (s->width != avctx->width && s->height != avctx->height) {
+        if (avcodec_check_dimensions(avctx, s->width, s->height) < 0)
+            return -1;
+        avcodec_set_dimensions(avctx, s->width, s->height);
+        if (s->frame.data[0])
+            avctx->release_buffer(avctx, &s->frame);
+    }
+
+    if (avctx->get_buffer(avctx, &s->frame) < 0){
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return -1;
+    }
+    memset(s->frame.data[0], 0, s->height * s->frame.linesize[0]);
+    s->frame.pict_type           = FF_I_TYPE;
+    s->frame.palette_has_changed = 1;
+
+    palette = (uint32_t*)s->frame.data[1];
+    if (etype == 1 && esize > 1 && *buf < 6) {
+        int idx = *buf;
+        npal = 4;
+        for (i = 0; i < npal; i++)
+            palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ];
+    } else if (etype == 2) {
+        npal = FFMIN(esize, 16);
+        for (i = 0; i < npal; i++)
+            palette[i] = ff_cga_palette[ FFMIN(buf[i], 16)];
+    } else if (etype == 3) {
+        npal = FFMIN(esize, 16);
+        for (i = 0; i < npal; i++)
+            palette[i] = ff_ega_palette[ FFMIN(buf[i], 63)];
+    } else if (etype == 4 || etype == 5) {
+        npal = FFMIN(esize / 3, 256);
+        for (i = 0; i < npal; i++)
+            palette[i] = AV_RB24(buf + i*3) << 2;
+    } else {
+        if (bpp == 1) {
+            npal = 2;
+            palette[0] = 0x000000;
+            palette[1] = 0xFFFFFF;
+        } else if (bpp == 2) {
+            npal = 4;
+            for (i = 0; i < npal; i++)
+                palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ];
+        } else {
+            npal = 16;
+            memcpy(palette, ff_cga_palette, npal * 4);
+        }
+    }
+    // fill remaining palette entries
+    memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4);
+    buf += esize;
+
+
+    x = 0;
+    y = s->height - 1;
+    plane = 0;
+    if (bytestream_get_le16(&buf)) {
+        while (buf_end - buf >= 6) {
+            const uint8_t *buf_pend = buf + FFMIN(AV_RL16(buf), buf_end - buf);
+            //ignore uncompressed block size reported at buf[2]
+            int marker = buf[4];
+            buf += 5;
+
+            while (plane < s->nb_planes && buf_pend - buf >= 1) {
+                int run = 1;
+                int val = *buf++;
+                if (val == marker) {
+                    run = *buf++;
+                    if (run == 0)
+                        run = bytestream_get_le16(&buf);
+                    val = *buf++;
+                }
+                if (buf > buf_end)
+                    break;
+
+                if (bits_per_plane == 8) {
+                    picmemset_8bpp(s, val, run, &x, &y);
+                    if (y < 0)
+                        break;
+                } else {
+                    picmemset(s, val, run, &x, &y, &plane, bits_per_plane);
+                }
+            }
+        }
+    } else {
+        av_log_ask_for_sample(s, "uncompressed image\n");
+        return buf_size;
+    }
+
+    *data_size = sizeof(AVFrame);
+    *(AVFrame*)data = s->frame;
+    return buf_size;
+}
+
+static av_cold int decode_end(AVCodecContext *avctx)
+{
+    PicContext *s = avctx->priv_data;
+    if (s->frame.data[0])
+        avctx->release_buffer(avctx, &s->frame);
+    return 0;
+}
+
+AVCodec pictor_decoder = {
+    "pictor",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_PICTOR,
+    sizeof(PicContext),
+    NULL,
+    NULL,
+    decode_end,
+    decode_frame,
+    CODEC_CAP_DR1,
+    .long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"),
+};