yading@10: /*
yading@10:  * Deluxe Paint Animation decoder
yading@10:  * Copyright (c) 2009 Peter Ross
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: /**
yading@10:  * @file
yading@10:  * Deluxe Paint Animation decoder
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "bytestream.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: typedef struct AnmContext {
yading@10:     AVFrame *frame;
yading@10:     int palette[AVPALETTE_COUNT];
yading@10:     GetByteContext gb;
yading@10:     int x;  ///< x coordinate position
yading@10: } AnmContext;
yading@10: 
yading@10: static av_cold int decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     AnmContext *s = avctx->priv_data;
yading@10:     int i;
yading@10: 
yading@10:     avctx->pix_fmt = AV_PIX_FMT_PAL8;
yading@10: 
yading@10:     s->frame = av_frame_alloc();
yading@10:     if (!s->frame)
yading@10:         return AVERROR(ENOMEM);
yading@10: 
yading@10:     bytestream2_init(&s->gb, avctx->extradata, avctx->extradata_size);
yading@10:     if (bytestream2_get_bytes_left(&s->gb) < 16 * 8 + 4 * 256)
yading@10:         return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     bytestream2_skipu(&s->gb, 16 * 8);
yading@10:     for (i = 0; i < 256; i++)
yading@10:         s->palette[i] = bytestream2_get_le32u(&s->gb);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Perform decode operation
yading@10:  * @param dst     pointer to destination image buffer
yading@10:  * @param dst_end pointer to end of destination image buffer
yading@10:  * @param gb GetByteContext (optional, see below)
yading@10:  * @param pixel Fill color (optional, see below)
yading@10:  * @param count Pixel count
yading@10:  * @param x Pointer to x-axis counter
yading@10:  * @param width Image width
yading@10:  * @param linesize Destination image buffer linesize
yading@10:  * @return non-zero if destination buffer is exhausted
yading@10:  *
yading@10:  * a copy operation is achieved when 'gb' is set
yading@10:  * a fill operation is achieved when 'gb' is null and pixel is >= 0
yading@10:  * a skip operation is achieved when 'gb' is null and pixel is < 0
yading@10:  */
yading@10: static inline int op(uint8_t **dst, const uint8_t *dst_end,
yading@10:                      GetByteContext *gb,
yading@10:                      int pixel, int count,
yading@10:                      int *x, int width, int linesize)
yading@10: {
yading@10:     int remaining = width - *x;
yading@10:     while(count > 0) {
yading@10:         int striplen = FFMIN(count, remaining);
yading@10:         if (gb) {
yading@10:             if (bytestream2_get_bytes_left(gb) < striplen)
yading@10:                 goto exhausted;
yading@10:             bytestream2_get_bufferu(gb, *dst, striplen);
yading@10:         } else if (pixel >= 0)
yading@10:             memset(*dst, pixel, striplen);
yading@10:         *dst      += striplen;
yading@10:         remaining -= striplen;
yading@10:         count     -= striplen;
yading@10:         if (remaining <= 0) {
yading@10:             *dst      += linesize - width;
yading@10:             remaining  = width;
yading@10:         }
yading@10:         if (linesize > 0) {
yading@10:             if (*dst >= dst_end) goto exhausted;
yading@10:         } else {
yading@10:             if (*dst <= dst_end) goto exhausted;
yading@10:         }
yading@10:     }
yading@10:     *x = width - remaining;
yading@10:     return 0;
yading@10: 
yading@10: exhausted:
yading@10:     *x = width - remaining;
yading@10:     return 1;
yading@10: }
yading@10: 
yading@10: static int decode_frame(AVCodecContext *avctx,
yading@10:                         void *data, int *got_frame,
yading@10:                         AVPacket *avpkt)
yading@10: {
yading@10:     AnmContext *s = avctx->priv_data;
yading@10:     const int buf_size = avpkt->size;
yading@10:     uint8_t *dst, *dst_end;
yading@10:     int count, ret;
yading@10: 
yading@10:     if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
yading@10:         return ret;
yading@10:     dst     = s->frame->data[0];
yading@10:     dst_end = s->frame->data[0] + s->frame->linesize[0]*avctx->height;
yading@10: 
yading@10:     bytestream2_init(&s->gb, avpkt->data, buf_size);
yading@10: 
yading@10:     if (bytestream2_get_byte(&s->gb) != 0x42) {
yading@10:         avpriv_request_sample(avctx, "Unknown record type");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     if (bytestream2_get_byte(&s->gb)) {
yading@10:         avpriv_request_sample(avctx, "Padding bytes");
yading@10:         return AVERROR_PATCHWELCOME;
yading@10:     }
yading@10:     bytestream2_skip(&s->gb, 2);
yading@10: 
yading@10:     s->x = 0;
yading@10:     do {
yading@10:         /* if statements are ordered by probability */
yading@10: #define OP(gb, pixel, count) \
yading@10:     op(&dst, dst_end, (gb), (pixel), (count), &s->x, avctx->width, s->frame->linesize[0])
yading@10: 
yading@10:         int type = bytestream2_get_byte(&s->gb);
yading@10:         count = type & 0x7F;
yading@10:         type >>= 7;
yading@10:         if (count) {
yading@10:             if (OP(type ? NULL : &s->gb, -1, count)) break;
yading@10:         } else if (!type) {
yading@10:             int pixel;
yading@10:             count = bytestream2_get_byte(&s->gb);  /* count==0 gives nop */
yading@10:             pixel = bytestream2_get_byte(&s->gb);
yading@10:             if (OP(NULL, pixel, count)) break;
yading@10:         } else {
yading@10:             int pixel;
yading@10:             type = bytestream2_get_le16(&s->gb);
yading@10:             count = type & 0x3FFF;
yading@10:             type >>= 14;
yading@10:             if (!count) {
yading@10:                 if (type == 0)
yading@10:                     break; // stop
yading@10:                 if (type == 2) {
yading@10:                     avpriv_request_sample(avctx, "Unknown opcode");
yading@10:                     return AVERROR_PATCHWELCOME;
yading@10:                 }
yading@10:                 continue;
yading@10:             }
yading@10:             pixel = type == 3 ? bytestream2_get_byte(&s->gb) : -1;
yading@10:             if (type == 1) count += 0x4000;
yading@10:             if (OP(type == 2 ? &s->gb : NULL, pixel, count)) break;
yading@10:         }
yading@10:     } while (bytestream2_get_bytes_left(&s->gb) > 0);
yading@10: 
yading@10:     memcpy(s->frame->data[1], s->palette, AVPALETTE_SIZE);
yading@10: 
yading@10:     *got_frame = 1;
yading@10:     if ((ret = av_frame_ref(data, s->frame)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     return buf_size;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     AnmContext *s = avctx->priv_data;
yading@10: 
yading@10:     av_frame_free(&s->frame);
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_anm_decoder = {
yading@10:     .name           = "anm",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_ANM,
yading@10:     .priv_data_size = sizeof(AnmContext),
yading@10:     .init           = decode_init,
yading@10:     .close          = decode_end,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
yading@10: };