[FFmpeg-devel] [PATCH v3 2/5] Interplay MVE: Refactor IP packet format
Hein-Pieter van Braam
hp at tmm.cx
Sun Jun 25 22:59:01 EEST 2017
Interplay MVE can contain up to three different frame formats. They
require different streams of information to render a frame. This patch
changes the IP packet format to prepare for the extra frame formats.
Signed-off-by: Hein-Pieter van Braam <hp at tmm.cx>
---
libavcodec/interplayvideo.c | 33 +++++++++++++++++++++-----------
libavformat/ipmovie.c | 46 ++++++++++++++++++++++++++++-----------------
2 files changed, 51 insertions(+), 28 deletions(-)
diff --git a/libavcodec/interplayvideo.c b/libavcodec/interplayvideo.c
index 7c69926..5dfb0d6 100644
--- a/libavcodec/interplayvideo.c
+++ b/libavcodec/interplayvideo.c
@@ -991,29 +991,40 @@ static int ipvideo_decode_frame(AVCodecContext *avctx,
AVFrame *frame = data;
int ret;
int send_buffer;
+ int frame_format;
+ int video_data_size;
if (av_packet_get_side_data(avpkt, AV_PKT_DATA_PARAM_CHANGE, NULL)) {
av_frame_unref(s->last_frame);
av_frame_unref(s->second_last_frame);
}
- if (buf_size < 3)
+ if (buf_size < 6)
return AVERROR_INVALIDDATA;
- send_buffer = AV_RL8(avpkt->data);
+ frame_format = AV_RL8(buf);
+ send_buffer = AV_RL8(buf + 1);
+ video_data_size = AV_RL16(buf + 2);
+ s->decoding_map_size = AV_RL16(buf + 4);
- /* decoding map contains 4 bits of information per 8x8 block */
- s->decoding_map_size = AV_RL16(avpkt->data + 1);
+ if (frame_format != 0x11)
+ av_log(avctx, AV_LOG_ERROR, "Frame type 0x%02X unsupported\n", frame_format);
- /* compressed buffer needs to be large enough to at least hold an entire
- * decoding map */
- if (buf_size < s->decoding_map_size + 2)
- return buf_size;
+ if (! s->decoding_map_size) {
+ av_log(avctx, AV_LOG_ERROR, "Empty decoding map\n");
+ return AVERROR_INVALIDDATA;
+ }
+ bytestream2_init(&s->stream_ptr, buf + 6, video_data_size);
- s->decoding_map = buf + 3;
- bytestream2_init(&s->stream_ptr, buf + 3 + s->decoding_map_size,
- buf_size - s->decoding_map_size - 3);
+ /* decoding map contains 4 bits of information per 8x8 block */
+ s->decoding_map = buf + 6 + video_data_size;
+
+ /* ensure we can't overread the packet */
+ if (buf_size < 6 + s->decoding_map_size + video_data_size) {
+ av_log(avctx, AV_LOG_ERROR, "Invalid IP packet size\n");
+ return AVERROR_INVALIDDATA;
+ }
if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
return ret;
diff --git a/libavformat/ipmovie.c b/libavformat/ipmovie.c
index 0705d33..a9ffca4 100644
--- a/libavformat/ipmovie.c
+++ b/libavformat/ipmovie.c
@@ -69,7 +69,7 @@
#define OPCODE_UNKNOWN_0E 0x0E
#define OPCODE_SET_DECODING_MAP 0x0F
#define OPCODE_UNKNOWN_10 0x10
-#define OPCODE_VIDEO_DATA 0x11
+#define OPCODE_VIDEO_DATA_11 0x11
#define OPCODE_UNKNOWN_12 0x12
#define OPCODE_UNKNOWN_13 0x13
#define OPCODE_UNKNOWN_14 0x14
@@ -92,6 +92,7 @@ typedef struct IPMVEContext {
int has_palette;
int changed;
uint8_t send_buffer;
+ uint8_t frame_format;
unsigned int audio_bits;
unsigned int audio_channels;
@@ -153,11 +154,11 @@ static int load_ipmovie_packet(IPMVEContext *s, AVIOContext *pb,
chunk_type = CHUNK_VIDEO;
- } else if (s->decode_map_chunk_offset) {
+ } else if (s->frame_format) {
- /* send the decode map, the video data, and the send_buffer flag together */
+ /* send the frame format, decode map, the video data, and the send_buffer flag together */
- if (av_new_packet(pkt, 3 + s->decode_map_chunk_size + s->video_chunk_size))
+ if (av_new_packet(pkt, 6 + s->decode_map_chunk_size + s->video_chunk_size))
return CHUNK_NOMEM;
if (s->has_palette) {
@@ -175,29 +176,38 @@ static int load_ipmovie_packet(IPMVEContext *s, AVIOContext *pb,
ff_add_param_change(pkt, 0, 0, 0, s->video_width, s->video_height);
s->changed = 0;
}
- pkt->pos= s->decode_map_chunk_offset;
- avio_seek(pb, s->decode_map_chunk_offset, SEEK_SET);
- s->decode_map_chunk_offset = 0;
- AV_WL8(pkt->data, s->send_buffer);
+ AV_WL8(pkt->data, s->frame_format);
+ AV_WL8(pkt->data + 1, s->send_buffer);
+ AV_WL16(pkt->data + 2, s->video_chunk_size);
+ AV_WL16(pkt->data + 4, s->decode_map_chunk_size);
+
+ s->frame_format = 0;
s->send_buffer = 0;
- AV_WL16(pkt->data + 1, s->decode_map_chunk_size);
- if (avio_read(pb, pkt->data + 3, s->decode_map_chunk_size) !=
- s->decode_map_chunk_size) {
+ pkt->pos = s->video_chunk_offset;
+ avio_seek(pb, s->video_chunk_offset, SEEK_SET);
+ s->video_chunk_offset = 0;
+
+ if (avio_read(pb, pkt->data + 6, s->video_chunk_size) !=
+ s->video_chunk_size) {
av_packet_unref(pkt);
return CHUNK_EOF;
}
- avio_seek(pb, s->video_chunk_offset, SEEK_SET);
- s->video_chunk_offset = 0;
+ pkt->pos = s->decode_map_chunk_offset;
+ avio_seek(pb, s->decode_map_chunk_offset, SEEK_SET);
+ s->decode_map_chunk_offset = 0;
- if (avio_read(pb, pkt->data + 3 + s->decode_map_chunk_size,
- s->video_chunk_size) != s->video_chunk_size) {
+ if (avio_read(pb, pkt->data + 6 + s->video_chunk_size,
+ s->decode_map_chunk_size) != s->decode_map_chunk_size) {
av_packet_unref(pkt);
return CHUNK_EOF;
}
+ s->video_chunk_size = 0;
+ s->decode_map_chunk_size = 0;
+
pkt->stream_index = s->video_stream_index;
pkt->pts = s->video_pts;
@@ -527,8 +537,9 @@ static int process_ipmovie_chunk(IPMVEContext *s, AVIOContext *pb,
avio_skip(pb, opcode_size);
break;
- case OPCODE_VIDEO_DATA:
+ case OPCODE_VIDEO_DATA_11:
av_log(s->avf, AV_LOG_TRACE, "set video data\n");
+ s->frame_format = 0x11;
/* log position and move on for now */
s->video_chunk_offset = avio_tell(pb);
@@ -595,7 +606,8 @@ static int ipmovie_read_header(AVFormatContext *s)
ipmovie->video_pts = ipmovie->audio_frame_count = 0;
ipmovie->audio_chunk_offset = ipmovie->video_chunk_offset =
ipmovie->decode_map_chunk_offset = 0;
- ipmovie->send_buffer = 0;
+ ipmovie->decode_map_chunk_size = ipmovie->video_chunk_size = 0;
+ ipmovie->send_buffer = ipmovie->frame_format = 0;
/* on the first read, this will position the stream at the first chunk */
ipmovie->next_chunk_offset = avio_tell(pb) + 4;
--
2.9.4
More information about the ffmpeg-devel
mailing list