HNM4/HNM4A demuxer & video decoder

Signed-off-by: Diego Biurrun <diego@biurrun.de>

1 files changed, 459 insertions, 0 deletions

diff --git a/libavcodec/hnm4video.c b/libavcodec/hnm4video.c
new file mode 100644
index 0000000000..b200e89a6a
--- /dev/null
+++ b/libavcodec/hnm4video.c
@@ -0,0 +1,459 @@
+/*
+ * Cryo Interactive Entertainment HNM4 video decoder
+ *
+ * Copyright (c) 2012 David Kment
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <string.h>
+
+#include "libavutil/internal.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/mem.h"
+#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+
+#define HNM4_CHUNK_ID_PL 19536
+#define HNM4_CHUNK_ID_IZ 23113
+#define HNM4_CHUNK_ID_IU 21833
+#define HNM4_CHUNK_ID_SD 17491
+
+typedef struct Hnm4VideoContext {
+    uint8_t version;
+    uint16_t width;
+    uint16_t height;
+    uint8_t *current;
+    uint8_t *previous;
+    uint8_t *buffer1;
+    uint8_t *buffer2;
+    uint8_t *processed;
+    uint32_t palette[256];
+} Hnm4VideoContext;
+
+static int getbit(GetByteContext *gb, uint32_t *bitbuf, int *bits)
+{
+    int ret;
+
+    if (!*bits) {
+        *bitbuf = bytestream2_get_le32(gb);
+        *bits = 32;
+    }
+
+    ret = *bitbuf >> 31;
+    *bitbuf <<= 1;
+    (*bits)--;
+
+    return ret;
+}
+
+static void unpack_intraframe(AVCodecContext *avctx, uint8_t *src,
+                              uint32_t size)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+    GetByteContext gb;
+    uint32_t bitbuf = 0, writeoffset = 0, count = 0;
+    uint16_t word;
+    int32_t offset;
+    int bits = 0;
+
+    bytestream2_init(&gb, src, size);
+
+    while (bytestream2_tell(&gb) < size) {
+        if (getbit(&gb, &bitbuf, &bits)) {
+            if (writeoffset >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR,
+                       "Attempting to write out of bounds");
+                break;
+            }
+            hnm->current[writeoffset++] = bytestream2_get_byte(&gb);
+        } else {
+            if (getbit(&gb, &bitbuf, &bits)) {
+                word   = bytestream2_get_le16(&gb);
+                count  = word & 0x07;
+                offset = (word >> 3) - 0x2000;
+                if (!count)
+                    count = bytestream2_get_byte(&gb);
+                if (!count)
+                    return;
+            } else {
+                count  = getbit(&gb, &bitbuf, &bits) * 2;
+                count += getbit(&gb, &bitbuf, &bits);
+                offset = bytestream2_get_byte(&gb) - 0x0100;
+            }
+            count  += 2;
+            offset += writeoffset;
+            if (offset < 0 || offset + count >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds");
+                break;
+            } else if (writeoffset + count >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR,
+                       "Attempting to write out of bounds");
+                break;
+            }
+            while (count--) {
+                hnm->current[writeoffset++] = hnm->current[offset++];
+            }
+        }
+    }
+}
+
+static void postprocess_current_frame(AVCodecContext *avctx)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+    uint32_t x, y, src_x, src_y;
+
+    for (y = 0; y < hnm->height; y++) {
+        src_y = y - (y % 2);
+        src_x = src_y * hnm->width + (y % 2);
+        for (x = 0; x < hnm->width; x++) {
+            hnm->processed[(y * hnm->width) + x] = hnm->current[src_x];
+            src_x += 2;
+        }
+    }
+}
+
+static void copy_processed_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+    uint8_t *src = hnm->processed;
+    uint8_t *dst = frame->data[0];
+    int y;
+
+    for (y = 0; y < hnm->height; y++) {
+        memcpy(dst, src, hnm->width);
+        src += hnm->width;
+        dst += frame->linesize[0];
+    }
+}
+
+static void decode_interframe_v4(AVCodecContext *avctx, uint8_t *src, uint32_t size)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+    GetByteContext gb;
+    uint32_t writeoffset = 0, count, left, offset;
+    uint8_t tag, previous, backline, backward, swap;
+
+    bytestream2_init(&gb, src, size);
+
+    while (bytestream2_tell(&gb) < size) {
+        count = bytestream2_peek_byte(&gb) & 0x1F;
+        if (count == 0) {
+            tag = bytestream2_get_byte(&gb) & 0xE0;
+            tag = tag >> 5;
+            if (tag == 0) {
+                hnm->current[writeoffset++] = bytestream2_get_byte(&gb);
+                hnm->current[writeoffset++] = bytestream2_get_byte(&gb);
+            } else if (tag == 1) {
+                writeoffset += bytestream2_get_byte(&gb) * 2;
+            } else if (tag == 2) {
+                count = bytestream2_get_le16(&gb);
+                count *= 2;
+                writeoffset += count;
+            } else if (tag == 3) {
+                count = bytestream2_get_byte(&gb) * 2;
+                while (count > 0) {
+                    hnm->current[writeoffset++] = bytestream2_peek_byte(&gb);
+                    count--;
+                }
+                bytestream2_skip(&gb, 1);
+            } else {
+                break;
+            }
+        } else {
+            previous = bytestream2_peek_byte(&gb) & 0x20;
+            backline = bytestream2_peek_byte(&gb) & 0x40;
+            backward = bytestream2_peek_byte(&gb) & 0x80;
+            bytestream2_skip(&gb, 1);
+            swap   = bytestream2_peek_byte(&gb) & 0x01;
+            offset = bytestream2_get_le16(&gb);
+            offset = (offset >> 1) & 0x7FFF;
+            offset = writeoffset + (offset * 2) - 0x8000;
+
+            left = count;
+
+            if (!backward && offset + count >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds");
+                break;
+            } else if (backward && offset >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds");
+                break;
+            } else if (writeoffset + count >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR,
+                       "Attempting to write out of bounds");
+                break;
+            }
+
+            if (previous) {
+                while (left > 0) {
+                    if (backline) {
+                        hnm->current[writeoffset++] = hnm->previous[offset - (2 * hnm->width) + 1];
+                        hnm->current[writeoffset++] = hnm->previous[offset++];
+                        offset++;
+                    } else {
+                        hnm->current[writeoffset++] = hnm->previous[offset++];
+                        hnm->current[writeoffset++] = hnm->previous[offset++];
+                    }
+                    if (backward)
+                        offset -= 4;
+                    left--;
+                }
+            } else {
+                while (left > 0) {
+                    if (backline) {
+                        hnm->current[writeoffset++] = hnm->current[offset - (2 * hnm->width) + 1];
+                        hnm->current[writeoffset++] = hnm->current[offset++];
+                        offset++;
+                    } else {
+                        hnm->current[writeoffset++] = hnm->current[offset++];
+                        hnm->current[writeoffset++] = hnm->current[offset++];
+                    }
+                    if (backward)
+                        offset -= 4;
+                    left--;
+                }
+            }
+
+            if (swap) {
+                left         = count;
+                writeoffset -= count * 2;
+                while (left > 0) {
+                    swap = hnm->current[writeoffset];
+                    hnm->current[writeoffset] = hnm->current[writeoffset + 1];
+                    hnm->current[writeoffset + 1] = swap;
+                    left--;
+                    writeoffset += 2;
+                }
+            }
+        }
+    }
+}
+
+static void decode_interframe_v4a(AVCodecContext *avctx, uint8_t *src,
+                                  uint32_t size)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+    GetByteContext gb;
+    uint32_t writeoffset = 0, offset;
+    uint8_t tag, count, previous, delta;
+
+    bytestream2_init(&gb, src, size);
+
+    while (bytestream2_tell(&gb) < size) {
+        count = bytestream2_peek_byte(&gb) & 0x3F;
+        if (count == 0) {
+            tag = bytestream2_get_byte(&gb) & 0xC0;
+            tag = tag >> 6;
+            if (tag == 0) {
+                writeoffset += bytestream2_get_byte(&gb);
+            } else if (tag == 1) {
+                hnm->current[writeoffset]              = bytestream2_get_byte(&gb);
+                hnm->current[writeoffset + hnm->width] = bytestream2_get_byte(&gb);
+                writeoffset++;
+            } else if (tag == 2) {
+                writeoffset += hnm->width;
+            } else if (tag == 3) {
+                break;
+            }
+        } else {
+            delta    = bytestream2_peek_byte(&gb) & 0x80;
+            previous = bytestream2_peek_byte(&gb) & 0x40;
+            bytestream2_skip(&gb, 1);
+
+            offset  = writeoffset;
+            offset += bytestream2_get_le16(&gb);
+
+            if (delta)
+                offset -= 0x10000;
+
+            if (offset + hnm->width + count >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds");
+                break;
+            } else if (writeoffset + hnm->width + count >= hnm->width * hnm->height) {
+                av_log(avctx, AV_LOG_ERROR, "Attempting to write out of bounds");
+                break;
+            }
+
+            if (previous) {
+                while (count > 0) {
+                    hnm->current[writeoffset]              = hnm->previous[offset];
+                    hnm->current[writeoffset + hnm->width] = hnm->previous[offset + hnm->width];
+                    writeoffset++;
+                    offset++;
+                    count--;
+                }
+            } else {
+                while (count > 0) {
+                    hnm->current[writeoffset]              = hnm->current[offset];
+                    hnm->current[writeoffset + hnm->width] = hnm->current[offset + hnm->width];
+                    writeoffset++;
+                    offset++;
+                    count--;
+                }
+            }
+        }
+    }
+}
+
+static void hnm_update_palette(AVCodecContext *avctx, uint8_t *src,
+                               uint32_t size)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+    GetByteContext gb;
+    uint8_t start, writeoffset;
+    uint16_t count;
+    int eight_bit_colors;
+
+    eight_bit_colors = src[7] & 0x80 && hnm->version == 0x4a;
+
+    // skip first 8 bytes
+    bytestream2_init(&gb, src + 8, size - 8);
+
+    while (bytestream2_tell(&gb) < size - 8) {
+        start = bytestream2_get_byte(&gb);
+        count = bytestream2_get_byte(&gb);
+        if (start == 255 && count == 255)
+            break;
+        if (count == 0)
+            count = 256;
+        writeoffset = start;
+        while (count > 0) {
+            hnm->palette[writeoffset] = bytestream2_get_be24(&gb);
+            if (!eight_bit_colors)
+                hnm->palette[writeoffset] <<= 2;
+            count--;
+            writeoffset++;
+        }
+    }
+}
+
+static void hnm_flip_buffers(Hnm4VideoContext *hnm)
+{
+    uint8_t *temp;
+
+    temp          = hnm->current;
+    hnm->current  = hnm->previous;
+    hnm->previous = temp;
+}
+
+static int hnm_decode_frame(AVCodecContext *avctx, void *data,
+                            int *got_frame, AVPacket *avpkt)
+{
+    AVFrame *frame = data;
+    Hnm4VideoContext *hnm = avctx->priv_data;
+    int ret;
+    uint16_t chunk_id;
+
+    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return ret;
+    }
+
+    chunk_id = AV_RL16(avpkt->data + 4);
+
+    if (chunk_id == HNM4_CHUNK_ID_PL) {
+        hnm_update_palette(avctx, avpkt->data, avpkt->size);
+        frame->palette_has_changed = 1;
+    } else if (chunk_id == HNM4_CHUNK_ID_IZ) {
+        unpack_intraframe(avctx, avpkt->data + 12, avpkt->size - 12);
+        memcpy(hnm->previous, hnm->current, hnm->width * hnm->height);
+        if (hnm->version == 0x4a)
+            memcpy(hnm->processed, hnm->current, hnm->width * hnm->height);
+        else
+            postprocess_current_frame(avctx);
+        copy_processed_frame(avctx, frame);
+        frame->pict_type = AV_PICTURE_TYPE_I;
+        frame->key_frame = 1;
+        memcpy(frame->data[1], hnm->palette, 256 * 4);
+        *got_frame = 1;
+    } else if (chunk_id == HNM4_CHUNK_ID_IU) {
+        if (hnm->version == 0x4a) {
+            decode_interframe_v4a(avctx, avpkt->data + 8, avpkt->size - 8);
+            memcpy(hnm->processed, hnm->current, hnm->width * hnm->height);
+        } else {
+            decode_interframe_v4(avctx, avpkt->data + 8, avpkt->size - 8);
+            postprocess_current_frame(avctx);
+        }
+        copy_processed_frame(avctx, frame);
+        frame->pict_type = AV_PICTURE_TYPE_P;
+        frame->key_frame = 0;
+        memcpy(frame->data[1], hnm->palette, 256 * 4);
+        *got_frame = 1;
+        hnm_flip_buffers(hnm);
+    } else {
+        av_log(avctx, AV_LOG_ERROR, "invalid chunk id: %d\n", chunk_id);
+        return AVERROR_INVALIDDATA;
+    }
+
+    return avpkt->size;
+}
+
+static av_cold int hnm_decode_init(AVCodecContext *avctx)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+
+    if (avctx->extradata_size < 1) {
+        av_log(avctx, AV_LOG_ERROR,
+               "Extradata missing, decoder requires version number\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    hnm->version   = avctx->extradata[0];
+    avctx->pix_fmt = AV_PIX_FMT_PAL8;
+    hnm->width     = avctx->width;
+    hnm->height    = avctx->height;
+    hnm->buffer1   = av_mallocz(avctx->width * avctx->height);
+    hnm->buffer2   = av_mallocz(avctx->width * avctx->height);
+    hnm->processed = av_mallocz(avctx->width * avctx->height);
+
+    if (!hnm->buffer1 || !hnm->buffer2 || !hnm->processed) {
+        av_log(avctx, AV_LOG_ERROR, "av_mallocz() failed\n");
+        av_freep(&hnm->buffer1);
+        av_freep(&hnm->buffer2);
+        av_freep(&hnm->processed);
+        return AVERROR(ENOMEM);
+    }
+
+    hnm->current  = hnm->buffer1;
+    hnm->previous = hnm->buffer2;
+
+    return 0;
+}
+
+static av_cold int hnm_decode_end(AVCodecContext *avctx)
+{
+    Hnm4VideoContext *hnm = avctx->priv_data;
+
+    av_freep(&hnm->buffer1);
+    av_freep(&hnm->buffer2);
+    av_freep(&hnm->processed);
+
+    return 0;
+}
+
+AVCodec ff_hnm4_video_decoder = {
+    .name           = "hnm4video",
+    .long_name      = NULL_IF_CONFIG_SMALL("HNM 4 video"),
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_HNM4_VIDEO,
+    .priv_data_size = sizeof(Hnm4VideoContext),
+    .init           = hnm_decode_init,
+    .close          = hnm_decode_end,
+    .decode         = hnm_decode_frame,
+    .capabilities   = CODEC_CAP_DR1,
+};