| /* |
| * 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 |
| * Pictor/PC Paint decoder |
| */ |
| |
| #include "libavutil/imgutils.h" |
| #include "libavutil/mem.h" |
| #include "avcodec.h" |
| #include "bytestream.h" |
| #include "cga_data.h" |
| #include "codec_internal.h" |
| #include "decode.h" |
| |
| typedef struct PicContext { |
| int width, height; |
| int nb_planes; |
| GetByteContext g; |
| } PicContext; |
| |
| static void picmemset_8bpp(PicContext *s, AVFrame *frame, int value, int run, |
| int *x, int *y) |
| { |
| while (run > 0) { |
| uint8_t *d = frame->data[0] + *y * 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, AVFrame *frame, unsigned value, int run, |
| int *x, int *y, int *plane, int bits_per_plane) |
| { |
| uint8_t *d; |
| int shift = *plane * bits_per_plane; |
| unsigned mask = ((1U << bits_per_plane) - 1) << shift; |
| int xl = *x; |
| int yl = *y; |
| int planel = *plane; |
| int pixels_per_value = 8/bits_per_plane; |
| value <<= shift; |
| |
| d = frame->data[0] + yl * frame->linesize[0]; |
| while (run > 0) { |
| int j; |
| for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) { |
| d[xl] |= (value >> j) & mask; |
| xl += 1; |
| while (xl == s->width) { |
| yl -= 1; |
| xl = 0; |
| if (yl < 0) { |
| yl = s->height - 1; |
| planel += 1; |
| if (planel >= s->nb_planes) |
| goto end; |
| value <<= bits_per_plane; |
| mask <<= bits_per_plane; |
| } |
| d = frame->data[0] + yl * frame->linesize[0]; |
| if (s->nb_planes == 1 && |
| run*pixels_per_value >= s->width && |
| pixels_per_value < (s->width / pixels_per_value * pixels_per_value) |
| ) { |
| for (; xl < pixels_per_value; xl ++) { |
| j = (j < bits_per_plane ? 8 : j) - bits_per_plane; |
| d[xl] |= (value >> j) & mask; |
| } |
| av_memcpy_backptr(d+xl, pixels_per_value, s->width - xl); |
| run -= s->width / pixels_per_value; |
| xl = s->width / pixels_per_value * pixels_per_value; |
| } |
| } |
| } |
| run--; |
| } |
| end: |
| *x = xl; |
| *y = yl; |
| *plane = planel; |
| } |
| |
| 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, AVFrame *frame, |
| int *got_frame, AVPacket *avpkt) |
| { |
| PicContext *s = avctx->priv_data; |
| uint32_t *palette; |
| int bits_per_plane, bpp, etype, esize, npal, pos_after_pal; |
| int i, x, y, plane, tmp, ret, val; |
| |
| bytestream2_init(&s->g, avpkt->data, avpkt->size); |
| |
| if (bytestream2_get_bytes_left(&s->g) < 11) |
| return AVERROR_INVALIDDATA; |
| |
| if (bytestream2_get_le16u(&s->g) != 0x1234) |
| return AVERROR_INVALIDDATA; |
| |
| s->width = bytestream2_get_le16u(&s->g); |
| s->height = bytestream2_get_le16u(&s->g); |
| bytestream2_skip(&s->g, 4); |
| tmp = bytestream2_get_byteu(&s->g); |
| bits_per_plane = tmp & 0xF; |
| s->nb_planes = (tmp >> 4) + 1; |
| bpp = bits_per_plane * s->nb_planes; |
| if (bits_per_plane > 8 || bpp < 1 || bpp > 32) { |
| avpriv_request_sample(avctx, "Unsupported bit depth"); |
| return AVERROR_PATCHWELCOME; |
| } |
| |
| if (bytestream2_peek_byte(&s->g) == 0xFF || bpp == 1 || bpp == 4 || bpp == 8) { |
| bytestream2_skip(&s->g, 2); |
| etype = bytestream2_get_le16(&s->g); |
| esize = bytestream2_get_le16(&s->g); |
| if (bytestream2_get_bytes_left(&s->g) < esize) |
| return AVERROR_INVALIDDATA; |
| } else { |
| etype = -1; |
| esize = 0; |
| } |
| |
| avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| |
| if (av_image_check_size(s->width, s->height, 0, avctx) < 0) |
| return -1; |
| |
| /* |
| There are 2 coding modes, RLE and RAW. |
| Undamaged RAW should be proportional to W*H and thus bigger than RLE |
| RLE codes the most compressed runs by |
| 1 byte for val (=marker) |
| 1 byte run (=0) |
| 2 bytes run |
| 1 byte val |
| thats 5 bytes and the maximum run we can code is 65535 |
| |
| The RLE decoder can exit prematurly but it does not on any image available |
| Based on this the formula is assumed correct for undamaged images. |
| If an image is found which exploits the special end |
| handling and breaks this formula then this needs to be adapted. |
| */ |
| if (bytestream2_get_bytes_left(&s->g) < s->width * s->height / 65535 * 5) |
| return AVERROR_INVALIDDATA; |
| |
| if (s->width != avctx->width || s->height != avctx->height) { |
| ret = ff_set_dimensions(avctx, s->width, s->height); |
| if (ret < 0) |
| return ret; |
| } |
| |
| if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
| return ret; |
| memset(frame->data[0], 0, s->height * frame->linesize[0]); |
| frame->pict_type = AV_PICTURE_TYPE_I; |
| #if FF_API_PALETTE_HAS_CHANGED |
| FF_DISABLE_DEPRECATION_WARNINGS |
| frame->palette_has_changed = 1; |
| FF_ENABLE_DEPRECATION_WARNINGS |
| #endif |
| |
| pos_after_pal = bytestream2_tell(&s->g) + esize; |
| palette = (uint32_t*)frame->data[1]; |
| if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) { |
| int idx = bytestream2_get_byte(&s->g); |
| 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++) { |
| int pal_idx = bytestream2_get_byte(&s->g); |
| palette[i] = ff_cga_palette[FFMIN(pal_idx, 15)]; |
| } |
| } else if (etype == 3) { |
| npal = FFMIN(esize, 16); |
| for (i = 0; i < npal; i++) { |
| int pal_idx = bytestream2_get_byte(&s->g); |
| palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)]; |
| } |
| } else if (etype == 4 || etype == 5) { |
| npal = FFMIN(esize / 3, 256); |
| for (i = 0; i < npal; i++) { |
| palette[i] = bytestream2_get_be24(&s->g) << 2; |
| palette[i] |= 0xFFU << 24 | palette[i] >> 6 & 0x30303; |
| } |
| } else { |
| if (bpp == 1) { |
| npal = 2; |
| palette[0] = 0xFF000000; |
| palette[1] = 0xFFFFFFFF; |
| } 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); |
| // skip remaining palette bytes |
| bytestream2_seek(&s->g, pos_after_pal, SEEK_SET); |
| |
| val = 0; |
| y = s->height - 1; |
| if (bytestream2_get_le16(&s->g)) { |
| x = 0; |
| plane = 0; |
| while (bytestream2_get_bytes_left(&s->g) >= 6) { |
| int stop_size, marker, t1, t2; |
| |
| t1 = bytestream2_get_bytes_left(&s->g); |
| t2 = bytestream2_get_le16(&s->g); |
| stop_size = t1 - FFMIN(t1, t2); |
| // ignore uncompressed block size |
| bytestream2_skip(&s->g, 2); |
| marker = bytestream2_get_byte(&s->g); |
| |
| while (plane < s->nb_planes && |
| bytestream2_get_bytes_left(&s->g) > stop_size) { |
| int run = 1; |
| val = bytestream2_get_byte(&s->g); |
| if (val == marker) { |
| run = bytestream2_get_byte(&s->g); |
| if (run == 0) |
| run = bytestream2_get_le16(&s->g); |
| val = bytestream2_get_byte(&s->g); |
| } |
| |
| if (bits_per_plane == 8) { |
| picmemset_8bpp(s, frame, val, run, &x, &y); |
| if (y < 0) |
| goto finish; |
| } else { |
| picmemset(s, frame, val, run, &x, &y, &plane, bits_per_plane); |
| } |
| } |
| } |
| |
| if (s->nb_planes - plane > 1) |
| return AVERROR_INVALIDDATA; |
| |
| if (plane < s->nb_planes && x < avctx->width) { |
| int run = (y + 1) * avctx->width - x; |
| if (bits_per_plane == 8) |
| picmemset_8bpp(s, frame, val, run, &x, &y); |
| else |
| picmemset(s, frame, val, run / (8 / bits_per_plane), &x, &y, &plane, bits_per_plane); |
| } |
| } else { |
| while (y >= 0 && bytestream2_get_bytes_left(&s->g) > 0) { |
| memcpy(frame->data[0] + y * frame->linesize[0], s->g.buffer, FFMIN(avctx->width, bytestream2_get_bytes_left(&s->g))); |
| bytestream2_skip(&s->g, avctx->width); |
| y--; |
| } |
| } |
| finish: |
| |
| *got_frame = 1; |
| return avpkt->size; |
| } |
| |
| const FFCodec ff_pictor_decoder = { |
| .p.name = "pictor", |
| CODEC_LONG_NAME("Pictor/PC Paint"), |
| .p.type = AVMEDIA_TYPE_VIDEO, |
| .p.id = AV_CODEC_ID_PICTOR, |
| .p.capabilities = AV_CODEC_CAP_DR1, |
| .priv_data_size = sizeof(PicContext), |
| FF_CODEC_DECODE_CB(decode_frame), |
| }; |
